NWA Weather Prediction Practice Test Questions
At sea level, water is ___________ times more dense than air.
784
The average sea level barometric pressure is defined as _____(1)______ mb. Actual barometric pressure will be _____(2)______ than sea level air pressure for locations above sea level.
(1) 1013, (2) lower
CAP is given in units of ______(1) ________ difference. This temperature difference is the amount of warming (or rather the weather conditions that will cause the parcel to no longer be colder than surrounding environment) required to produce no CAP. When the CAP is less than _____(2)_______, storms are likely to develop shortly when the only parameter holding back convection is the CAP.
(1) Celsius, (2) 2.0
A sea breeze front will bring in ____(1)_____ temperatures inland. The sea breeze occurs during the ____(2)_____. - (1) Cooler, (2) night - (1) Cooler, (2) day - (1) Warmer, (2) night - (1) Warmer, (2) day
(1) Cooler, (2) day
Dew is most likely to first form on substances that are _____(1)______ than surrounding objects and have a ______(2)________ dewpoint immediately around the object. - (1) Warmer, (2) higher - (1) Warmer, (2) lower - (1) Cooler, (2) lower - (1) Cooler, (2) higher
(1) Cooler, (2) higher
If colder air and warmer air are advecting toward each other on a constant pressure surface, the air that will lift over the other will be the ____(1)_____ air because the air being lifted is ____(2)____ dense.
(1) Warmer, (2) less
Evaporational cooling _____(1)_____ latent heat and therefore _____(2)_____ the air. - (1) releases, (2) warms - (1) releases, (2) cools - (1) absorbs, (2) warms - (1) absorbs, (2) cools
(1) absorbs, (2) cools
You can think of a vorticity max as a(n) "_______________" and a vorticity lobe as a(n) "________________".
(1) bulls eye, (2) elongated bulls eye
When the 1000 the 500 millibar thicknesses are decreasing over time a forecaster would expect ______(1)_________. The models are best at predicting ______(2)______ precipitation amounts.
(1) cold air advection, (2) dynamically induced
The pressure decreases more rapidly with height in a _____(1)______ air mass. A ____(2)_____ air mass will have high 1000 to 500 mb thickness values.
(1) cold, (2) warm
A katabatic wind is a flow from high toward lower elevations in which the wind coming from the higher elevation is ____(1)______ in temperature than the air it is displacing even though it is sinking adiabatically. A sudden increase in friction will cause the air to be more ____(2)_____.
(1) colder, (2) ageostrophic
At the leading edge of outflow boundaries ______(1)________ occurs. Outflow boundaries promote _____(2)______ air as they move along the earth's surface.
(1) convergence, (2) rising
A trough over the forecast area will generally bring ____(1)_____ temperatures. A trough will ___(2)____ if the winds are stronger on the downstream side of the trough as compared to the upstream side.
(1) cooler, (2) lift
Cloud cover generally acts to make day time temperatures _____(1)______ than they would be without cloud cover. Cloud cover generally acts to make night time temperatures _____(2)______ than they would be without cloud cover.
(1) cooler, (2) warmer
Precipitation usually results in a _____(1)______ of the air it falls through. If precipitation falls during the day, the overnight low temperature after the precipitation will tend to be ____(2)_____ than if no precipitation occurred.
(1) cooling, (2) warmer
As dewpoint depression increases, the relative humidity ____(1)_____ and the evaporational potential _____(2)_______. - (1) increases, (2) increases - (1) decreases, (2) decreases - (1) increases, (2) decreases - (1) decreases, (2) increases
(1) decreases, (2) increases
A(n) ____(1)_____ wind will usually promote warmer temperatures if upstream air is not too much colder. On a clear night with no temperature advection, the low temperature will tend to be _____(2)_____ when winds are weaker.
(1) downslope, (2) cooler
When determining the Lifted Condensation Level, the lifting below the LCL is at the _____(1)______ adiabatic lapse rate. When unsaturated air rises, the dewpoint decreases by ____(2)_____ with height.
(1) dry, (2) 2 C per kilometer
Warm air advection in the low levels of the troposphere causes rising air. This is because warm air ____(1)_____, creating a higher thickness, which in turn causes the air to rise. Any low level density boundary will lead to rising motion if ______(2)______ occurs along that low-level boundary.
(1) expands, (2) convergence
In the ______(1)________ season temperatures cool off most rapidly in the mid-latitudes when comparing the early part of the season to the later part of the season. The noon sun angle is highest in _____(2)_______ summer.
(1) fall, (2) early
A low pressure system that is weakening will be ______(1)________. A low pressure system that is strengthening will be ______(2)_________.
(1) filling, (2) deepening
If the central pressure of a low pressure system is rising in pressure it is said to be _____(1)_____. If a trough is becoming less amplified and moving into higher latitudes it is said to be _____(2)_____.
(1) filling, (2) lifting
Evaporational cooling is most common in the ________(1)__________. Drier air tends to be associated with the ________(2)___________. - (1) rear flank downdraft, (2) rear flank downdraft - (1) forward flank downdraft, (2) forward flank downdraft - (1) rear flank downdraft, (2) forward flank downdraft - (1) forward flank downdraft, (2) rear flank downdraft
(1) forward flank downdraft, (2) rear flank downdraft
On radar, typical snow tends to have a ____(1)_____ gradient and a ____(2)_____ reflectivity.
(1) fuzzy, (2) light
Hail from a thunderstorm is most likely to reach the surface in _____(1)_______. Hail tends to be _____(2)______ in size once reaching the surface than it was at 700 mb on its ride to the surface.
(1) high elevation regions, (2) smaller
Rapid height falls on upper level charts indicate that _____(1)______ weather is likely approaching. Rapid surface pressure rises at the surface indicate that _____(2)______ weather is likely approaching. - (1) tranquil, (2) tranquil - (1) inclement, (2) tranquil - (1) tranquil, (2) inclement - (1) inclement, (2) inclement
(1) inclement, (2) tranquil
When strong low level warm air advection occurs, the 700 mb, 500 mb and 300 mb height contour values will likely _____(1)______. The 500 mb level is closest to ____(2)_____ kilometers.
(1) increase, (2) 5.5
(1) temperature increase with height, (2) lapse rate between dry and moist adiabatic rate, (3) Layer with a constant temperature with height, (4) Lapse rate a saturated lifting parcel of air takes.
(1) inversion, (2) conditional instability, (3) isothermal lapse rate, (4) wet adiabatic lapse rate
As the sun rises in the sky during the morning hours it progressively passes through a _____(1)_____ distance of atmosphere in order for the radiation to make it to the earth's surface. When the sun or moon are within about 10 degrees of the horizon, they look much ______(2)_______ than they do higher in the sky.
(1) lesser, (2) bigger
The polar jet stream divides _______(1)________. If the wind speeds are much higher on the left side of a trough that trough can be expected to _____(2)______.
(1) mid-latitude air from polar air, (2) dig
Air is a very ____(1)______ absorber of solar radiation while objects on the earth's surface are much better at absorbing. Even snow with its very high albedo and reflective ability is _____(2)______ absorbing of solar radiation than the air.
(1) poor, (2) more
A global wind moving toward the North in the Northern Hemisphere will be deflected to the _____(1)______ of the path of motion by the Coriolis force. A global wind moving toward the North in the Southern Hemisphere will be deflected to the _____(2)______ of the path of motion by the Coriolis force. - (1) left, (2) left - (1) right, (2) right - (1) left, (2) right - (1) right, (2) left
(1) right, (2) left
The omega block tends to have cooler weather on the ____(1)_____ side of the omega block due to northerly winds. The weather under the center of an omega block tends to be _____(2)_____.
(1) right, (2) nice
DPVA contributes to ______(1)________. PDVA ______(2)________ the troposphere and thus lowers heights aloft.
(1) rising air, (2) cools
PVA promotes ______(1)_______ air and _____(2)_____ height surfaces aloft.
(1) rising, (2) falling
At the same above freezing temperature, snowflakes that fall through dry air will melt _____(1)_____ than snowflakes that fall through moist air. When a snowflake falls through saturated above freezing air, most of the latent heat absorbed by the snowflake will be due to ______(2)________.
(1) slower, (2) melting
Gravity waves propagate through ____(1)______ atmospheric layers. In a gravity wave, the ____(2)____ moving region is the most favorable region for cloud development.
(1) stable, (2) upward
Occluded mid-latitude cyclone systems will generally be _______(1)_______ with height. Strong developing mid-latitude cyclone systems will generally be ______(2)_________ with height.
(1) stacked, (2) vertically tilted
The weather a certain location will experience is likely to be influenced by the _____(1)______ weather conditions. As a boat moves in a river current it moves toward _____(2)_______. - (1) upstream, (2) downstream - (1) downstream, (2) upstream - (1) upstream, (2) upstream - (1) downstream, (2) downstream
(1) upstream, (2) downstream
The type of vorticity displayed on the 500-mb pressure surface is ____(1)_____. The type of vorticity produced from changes in wind speed and direction with height is _____(2)_____.
(1) vertical vorticity, (2) horizontal vorticity
An environment that is ____(1)_____ and ____(2)_____ in the low levels and cool and dry in the middle levels is convectively unstable.
(1) warm, (2) moist
An increase of longwave radiation absorbed by the earth's surface due to an increase of clouds in the overnight hours will tend to cause the temperature to be _____(1)______ than they otherwise would be. During the day, clouds act as a _____(2)______ agent.
(1) warmer, (2) cooling
While evaporation is a cooling agent, sunshine is a _____(1)_____ agent. If clouds give way to sun, temperature are likely to _____(2)______ quickly.
(1) warming, (2) warm
The most important greenhouse gas to a weather forecaster is ____(1)______. In equal quantities, _____(2)_______ is the more powerful greenhouse gas of the two.
(1) water vapor, (2) carbon dioxide
Which of the following will accurately calculate the relative humidity? - (Saturation vapor pressure divided by actual vapor pressure) times 100% - (Dewpoint value is Celsius divided by temperature value in Celsius) times 100% - (Vapor pressure divided by saturation vapor pressure) times 100% - (Temperature value is Celsius divided by dewpoint value in Celsius) times 100%
(Vapor pressure divided by saturation vapor pressure) times 100%
What is the world record for the coldest temperature measured on Earth's surface?
-129 F
At what temperature is the temperature the same on both the Celsius and Fahrenheit scale when converting one to the other. - 0 - -20 - -40 - -273
-40
At what temperature is it too cold to snow? - 0 C - 0 F - 0 K
0 K
What is the threshold size between a drizzle drop and a rain drop?
0.5 millimeters
A one degree temperature change on the Fahrenheit scale is equal a _______________ degree change on the Celsius scale.
0.56
A mile per hour is equal to ________ nautical miles per hour. - 2 - 1.5 - 1.15 - 0.87
0.87
Thunder travels at the speed of sound which is nearest to:
1 mile every 5 seconds
At standard temperature and pressure the density of air is _______ kilograms per meter cubed.
1.275
If the maximum unambiguous range is 190 miles and a storm is located 200 miles from the radar, what distance from the radar will the echo from this storm be erronously displayed:
10 miles
Given the data below, what is the K Index? 850 mb Temperature = 18 C 500 mb Temperature = -5 C 850 mb Dewpoint = 10 C 700 mb Dewpoint Depression = 22 units of C
11
If no lifting mechanisms are present then daytime heating will likely not be enough to initiate thunderstorm development if the 700 mb temperature is higher than a critical value of ____ C.
12
The numbers 956 next to a station plot at 700 millibars is what value in geopotential meters? Think of the average 700 millibar height in geopotential meters before looking at the choices.
2,956 geopotential meters
Bombogenesis is defined as a mid-latitude cyclone that drops in surface barometric pressure by ______________ or more millibars in a 24-hour period. - 12 - 20 - 24 - 50
24
One saturated air parcel with a temperature of 10 ° C has a saturation mixing ratio of 7 grams per kilogram; A second air parcel with a temperature of 20 ° C has a saturation mixing ratio of 14 grams per kilogram; From this information, what is the most likely saturation mixing ratio of a parcel of air at 30 ° C? Warmer air holds exponentially more water vapor, therefore the temperature/saturation mixing ratio relationship is not linear.
26.5 grams per kilogram
1013.25 mb = ___________ inches of mercury.
29.92
Suppose the mean temperature for a day is 35 F. The number of heating degree days is using DD-65 is:
30
If cold air advection occurs at all level of the troposphere, the pressure level that will experience the greatest height falls will be at: - The surface - 850 mb - 500 mb - 300 mb
300 mb
When the surface temperature and dewpoint are several degrees above freezing and moderate to heavy snow starts to fall the temperature will often fall to ________ and then stay there during the snow event.
32 F
If the temperature is 45 F with a dewpoint of 10 F and heavy rain starts falling, what is the most likely temperature after complete evaporational cooling? Use 1/3 rule - 37 F - 35 F - 33 F - 31 F
33 F
Minimum tropical storm force wind is ________________ miles per hour while the minimum hurricane force wind is _______________ miles per hour.
39; 74
Which LI value is the most stable? - 4 - 0 - -4 - -8
4
A parcel of air has a dewpoint of 8 C. What is the dewpoint of this parcel after the parcel rises 2 kilometers and remains unsaturated.
4 C
If it is 4 Z in Boston then what Z time is it in Los Angeles?
4 Z
A wet snow will have a snow to liquid equivalent of:
4 to 1
The surface wind speed is 10 m/s while the wind speed 3 km up is 20 m/s. What is the 0 to 3 km shear?
4.3
The volume of a spherical raindrop is:
4/3*PI*radius^3
The formula of a sphere is: - Pi*diameter - 4/3*Pi*(radius)^3 - 4*Pi*(radius)^2 - length*width*height
4/3*Pi*(radius)^3
25 C is equal to _________ F. - 50 - 68 - 77 - 86
77
Suppose a parcel of air at the surface has a temperature of 50 ° F with a dewpoint of 30 ° F. As it begins to rain heavily into the parcel, what is the wet-bulb temperature most likely to be after complete evaporational cooling?
43 ° F
A CAPE of 1000 J/kg correlates into a maximum updraft speed of ________ meters per second.
44.7
What is the mass of Earth's atmosphere?
5.27 * 10^18 kilograms
If the 700 mb temperature is -3 C and the 700 mb height is 2,980 meters while the 500 mb temperature is -17 C and the 500 mb height is 5,370 meters, what is the L57 in C/km?
5.9
Which of the following operational forecast panels is used to analyze vorticity advection? - 850 millibar forecast panel - 500 millibar forecast panel - 700 millibar forecast panel - 300 millibar forecast panel
500 millibar forecast panel
There is a temperature that has the same numerical value on both the Fahrenheit and Kelvin temperature scales. What is this value?
574.25
You are in New York City for New Year's and the time has just changed to the year 2000. What time is it in Zulu (Z) time?
5Z JAN 01 2000
The average environmental lapse rate which is defined as the average rate the temperature decreases with height in the troposphere is near ________ degrees C/km. - 4.5 - 5.5 - 6.5 - 7.5
6.5
Suppose a baseball player who is running at 10 mph throws a baseball at 50 mph in the same direction he is running. Relative to the running baseball player the ball is moving away at 50 mph. However, a stationary baseball player that catches the throw detects the ball approaching at ___________ mph. - 40 - 50 - 60 - 100
60
Suppose it is 70 ° F in Dallas and 40 ° F in Oklahoma City. The distance between these cities is 150 miles. By using linear interpolation, what is the likely temperature 50 miles north of Dallas.
60 ° F
Given the data below, what is the Total Totals Index? 850 mb Temperature = 18 C 500 mb Temperature = -17.5 C 850 mb Dewpoint = 12 C
65
A 100 mile per hour wind is how many knots?
87 knots
How much faster approximately does light travel than sound?
882,000 times as fast
Unsaturated air rises at the dry adiabatic lapse rate which is ___________ ° C per kilometer. This is also the same numerical value as the gravitational force constant in meters per second squared.
9.8
What is the difference between a closed low and a cut-off low? - A closed low is embedded within the upper level jet stream flow while a cut-off low is not - A closed low is a maturing mid-latitude cyclone while a cut-off low is occluded - A closed low has significant vorticity and thermal advection associated with it while a cut-off low does not - A closed low occurs in the mid-latitudes while a cut-off low occurs in the tropics
A closed low is embedded within the upper level jet stream flow while a cut-off low is not
If the earth did not rotate, which of the following would be most true?: - The same side of the Earth would always face the sun - The global circulation patterns would be the same as they are on Earth now - The Coriolis deflection would be more than it currently is on Earth - A day would be the same length of time as a year
A day would be the same length of time as a year
Which of the following statements is FALSE? - The azimuth is the compass direction a hydrometeor is from the radar site - A doppler radar detects the actual wind speed in all directions from the radar - The range height indicator can be used to measure cloud top heights - The plan position indicator can to used to determine how far a hydrometeor is from the radar site.
A doppler radar detects the actual wind speed in all directions from the radar
Define V-notch:
A fanning of clouds downstream from the burst point of convective thunderstorms
What is a dirty high pressure? - A high pressure that produces very hot and dusty weather - A high pressure that has widespread clouds, precipitation and/or fog within its domain - A strong high pressure that stalls over a region for a significant number of days - A high pressure region that increases smog over a city
A high pressure that has widespread clouds, precipitation and/or fog within its domain
For synoptic scale precipitation to occur through dynamic (forced) ascent there needs to be saturated air and ____________. - A lifting mechanism - An unstable troposphere - Synoptic scale subsidence - Strong speed and directional wind shear
A lifting mechanism
Which of the following is an example of an adiabatic process: - A parcel of air warming as it sinks - Sun shine warming the earth's surface - Evaporational cooling within a parcel of air - The soil evaporating moisture into the boundary layer
A parcel of air warming as it sinks
The word MONSOON as it applies to climatology refers to:
A seasonal reversal in wind direction and pressure distribution
The Showalter Index is superior to using the Lifted Index when: - The PBL is very warm and humid - The forecast area is in the warm sector of a mid-latitude cyclone - A shallow region of cold air is in the lower troposphere - In desert regions
A shallow region of cold air is in the lower troposphere
What is a "classic event"? - A situation where are the ingredients come together for a particular note worthy weather event - It is a particular type of supercell thunderstorm that commonly has tornadoes - A weather event that is very similar to a weather event that - Any weather event that occurs on a global scale such as El Nino
A situation where are the ingredients come together for a particular note worthy weather event
Which individual snow flake will melt the fastest when it falls on a 33 F substance? - A snow flake that falls on a road - A snow flake that falls on water - A snow flake that falls on grass - A snow flake that falls on a car
A snow flake that falls on water
A TVS icon is displayed on radar where: - Large hail is possible - Strong convective wind gusts are possible - A tornado is possible - Lightning is possible
A tornado is possible
An S-shaped radial velocity pattern on Doppler radar indicates: - A veering wind and warm air advection - A veering wind and cold air advection - A backing wind and warm air advection - A backing wind and cold air advection
A veering wind and warm air advection
A chinook wind causes: - A cooling and moistening of air - A cooling and drying of air - A warming and moistening of air - A warming and drying of air
A warming and drying of air
A downsloping wind is most likely to cause: - A cooling of temperature - A warming of temperature - An increased threat for precipitation - An increase in the surface relative humidity
A warming of temperature
What is "return flow"? - A wind shift back to the south that brings in higher temperatures and dewpoints - A wind shift back to the north that brings in lower temperatures and dewpoints - A flow of air that exits the forecast region and then comes back - A flow of air that is in circles
A wind shift back to the south that brings in higher temperatures and dewpoints
The surface temperature is 32 F. All of the following will tend to help cool the temperature during a precipitation event except: - Above freezing rain drops - Supercooled rain drops - Frozen precipitation - Melting and evaporation from precipitation
Above freezing rain drops
Which of the following is false: - Earth vorticity is always positive except at the equator - Curvature vorticity results from a changing in wind direction over time - Absolute vorticity is always positive - Shear vorticity is a change in wind speed over a change in distance
Absolute vorticity is always positive
________________ refers to the horizontal transport of air while _______________ is the vertical transport of air.
Advection, convection
Forecasting using the convective temperature is most relevant in: - Forced lifting thunderstorm situations - Severe thunderstorm situations - Tropical storm situations - Air mass thunderstorm situations
Air mass thunderstorm situations
Differential advection is:
Air masses advecting over each other
How can a radar operator differentiate between real precipitation and false reflectivity echoes? - Often precipitation areas are organized and move while false echoes do not - Often false echoes are grainy and have unrealistic precipitation gradients of intensity - Other radars, satellite data and surface observations can be used to aid to identify if precipitation is real - By knowing the temperature and moisture structure of the troposphere the meteorologist can determine how likely ducting is
All
The accumulation of snow is a function of: - Duration - Intensity - Snow to liquid ratio
All
The jet stream can make a storm more severe by: - Increasing upper level moisture - Causing the updraft to be vertically stacked - Increasing the amount of wind shear
All
Why does snow tend to accumulate better in grassy areas as compared to roads. - Vehicle traffic and melting agents helps melt snow on the roads - Vegetation is often better exposed to the cold air and absorbs excess moisture - Vegetation shadows some solar radiation and provides a wind trap
All
Many cold fronts will have the following feature: - Wind shift - Temperature gradient - Surface pressure trough
All apply
A region of low values of precipitation surrounding by higher values of precipitation can be explained by a: - Reduced amount of low level convergence - Reduced amount of adequate moisture - Reduced amount of lifting
All are possible
A sustained period of heavy rain at a location is promoted by: - A strong downdraft - A large volume of moisture entering an updraft - Slow movement of storm
All are true
CAPE is used to assess: - Hail potential - Thunderstorm potential - Updraft strength
All are true
The MW (Maximum Wind) parameter value can be used to determine: - Highest wind speed on the sounding - Pressure level with highest wind speed - Height of the highest wind speed
All are true
This on radar indicates a flooding potential: - Consistently heavy rain - Training of storms - Very intense slow moving thunderstorms
All are true
When it comes to fronts, it is important to forecast: - When the front will pass through the forecast area - How much lifting will occur along the front - How much temperature advection will occur behind the front
All are true
When using percentage of precipitation chance and storm probabilities it is a good idea to add the following information to the probability: - Descriptive terms for how much of the forecast region could have precipitation or storms - The character of the precipitation such as type, intensity, movement and duration - When the precipitation or storms are most likely to occur
All are true
Which is the following is true a friction? - It slows the wind down from what it would be if the wind was geostrophic - Friction causes an imbalance between the pressure gradient and Coriolis forces - Friction can release energy through noise, vibrations and motions
All are true
Which of the following is true?: - A CAP of 5 is a strong cap - Surface based lifted parcels will rise on their own once they have penetrated the level of free convection - A cap could either enhance a severe storm event or prevent it from occurring all together
All are true
Which statement is true regarding the temperature of a thermometer placed in the backyard. - When the thermometer is too close to the house, warmer or cooler air from the house can contaminate the measurement - A thermometer in the sunlight will read much too high. The official temperature measurement is made in the shade - The thermometer should be about 5 to 6 feet off the ground since the official measurements are taken near this height. Thermometer may read too warm in the day if it is too close to the ground and too cool during the night if it is too close to the ground
All are true
Why are forest fires common in the summer? - Warm temperatures evaporate moisture away from the surface - Increased amounts of lightning - Dry vegetation during warm dry weather
All are true
Why are hurricanes difficult to predict? - Not as much data over ocean areas - Lack of good mesoscale data - Very subtle changes in the environment can significantly change the direction and speed the hurricane moves
All are true
Which process will modify an air mass after it moves away from the source region?: - Solar radiation - Significant difference between air and soil temperature - Evaporational cooling - Cloud cover
All can modify an air mass
If uplift produces clouds but not precipitation at the surface, a possible reason why no precipitation occurred at the surface is due to the: - Uplift not being strong enough - Initial column layer relative humidity not being high enough - The air the precipitation falls into being too dry - All of the above
All of the above
The 0 C isotherm can move across the surface or a pressure surface through: - Thermal advection - Evaporational cooling - Radiational cooling - All of the above
All of the above
Storms will often form first where: - The cap is the weakest - The boundary layer convergence is the strongest - The boundary layer Theta-E is the highest
All options are true
The freezing level is important to know in: - Severe weather forecast situations - Winter weather forecast situations - Icing situations on aircraft
All true
This is a current state of the troposphere as measured by weather sensors to produce a chart: - Prog - Model - Image - Analysis
Analysis
To see how well a model initializes, compare the model initialization to the: - Model initialization of another model - Analysis chart of the actual data - Same models initialization from when a similar weather set-up occurred - Consensus initialization of several models
Analysis chart of the actual data
What is the feature at "A"? - Flanking line - Mammatus - Anvil - Outflow boundary
Anvil
Much of the lighter reflectivity on radar that is downwind from a supercell is the result of: - Anvil blowoff - Suspended hail - Strong shear - Anomalous propagation
Anvil blowoff
How does a squall line look at radar? - As a region of scattered supercell storms - As a region of light rain - As an elongated band of strong storms
As an elongated band of strong storms
The official definition of a "white Christmas" is: - Any amount of snow falling on Christmas day - At least 1 inch of snow of the ground on Christmas day - Snow falling at least half the day on Christmas day - Cloudy skies on Christmas day
At least 1 inch of snow of the ground on Christmas day
A city in the Southeast U.S. that experiences the most significant cold air damming events in winter is: - Dallas, TX - Atlanta, GA - Little Rock, AR - New Orleans, LA
Atlanta, GA
A ____________ cold front is a cold front that approaches from the east or northeast. The winds behind this front come from those same directions. This type of front can occur when the clockwise rotation around high pressure brings colder air toward the south and west. This type of front can also occur to the north of a developing area of low pressure.
Back door
Suppose a lab refrigerator holds a constant temperature of 38.0 F. A temperature sensor is tested 10 times in the refrigerator. The temperatures from the test yield the temperatures of : 39.2, 39.3, 39.1, 39.0, 39.1, 39.3, 39.2, 39.1, 39.2, 39.2. The sensor has ______________________.
Bad accuracy and good precision
The safest location to be during a tornado is a(n): - Mobile home - Car - Attic - Bank vault
Bank vault
This is a synoptic environment with fronts and mid-latitude cyclones: - Baroclinic - Barotropic
Baroclinic
When there is a balance between the upward pressure gradient force and the downward force of gravity, the atmosphere is said to be in ______________ balance.
Baroclinic
When the conditions set up for strong radiational cooling the low temperature will often fall ___________ what forecast model consensus indicates. Conditions for strong radiational cooling at night include clear skies, a long night, dry air, snow on the ground and light wind.
Below
A red sky at night in which the western part of the sky is clear and the eastern part of the sky is cloudy means: - Better weather, sailor's delight - Approaching bad weather, sailor's warning
Better weather, sailor's delight
Which of the following has the lowest albedo? - Snow - Black top - Sand - Forest
Black top
(Statement 1) A point is a position in space that has no area and no volume. (Statement 2) The precision of a measurement can always be more precise since there can be an infinite amount of numbers further to the right of the decimal point for any measurement. T/F
Both True
(Statement 1) As the dewpoint increases that indicates the amount of moisture in the air is increasing. (Statement 2) As the relative humidity increases that indicate the air is becoming closer to saturation. T/F
Both True
(Statement 1) During the daytime hours, a lighter wind will typically lead to a warmer high temperature. (Statement 2) During the overnight hours, a lighter wind will typically lead to a cooler low temperature. T/F
Both True
(Statement 1) Ground clutter causes an overestimation of reflectivity. (Statement 2) Attenuation causes an underestimation of reflectivity. T/F
Both True
(Statement 1) It is a good idea to remind that storms and severe thunderstorms often produce tornadoes even when no tornado warning is out yet. (Statement 2) Be careful about zooming in too close for too long on a storm when running the radar. Keep a close watch on all the viewing area. T/F
Both True
(Statement 1) The temperature minus the dewpoint is the dewpoint depression. (Statement 2) Upper air temperatures are usually given in degrees Celsius. T/F
Both True
(Statement 1) To reduce velocity aliasing on Doppler radar, increase the pulse repetition frequency. (Statement 2) To reduce range aliasing on radar, decrease the pulse repetition frequency. T/F
Both True
(Statement 1) Mesoscale regions of high dynamic Upward Vertical Velocity will warm the troposphere more than the models indicate for the synoptic scale. (Statement 2) Thickness (TH) is the distance between two pressure levels in the troposphere. T/F
Both are True
(Statement 1) A region of enhanced wind flow within the jet stream is termed a jet streak. (Statement 2) The jet stream has waves within it of troughs and ridges. T/F
Both are true
(Statement 1) A south wind in the boundary layer and a west wind higher aloft is an example of a backing wind. (Statement 2) A veering wind is associated with warm air advection especially in the middle latitudes near mid-latitude cyclones. T/F
Both are true
(Statement 1) At the surface a polar vortex will have high pressure. (Statement 2) The polar vortex aloft propagates toward where the polar air mass moves. T/F
Both are true
(Statement 1) Sleet often occurs in the transition from rain to snow or vice versa. (Statement 2) There needs to be above freezing temperatures in a layer aloft in order for sleet to be possible. T/F
Both are true
(Statement 1) Snow can occur if the 850 mb temperature is 0 C. (Statement 2) Snow can occur when low level warm air advection occurs. T/F
Both are true
(Statement 1) The initial 850 to 500 mb relative humidity needs to be high in order for thunderstorms to occur. (Statement 2) The 850 to 500 mb relative humidity tends to be high around fronts, low pressure systems and other regions where deep dynamic lifting occurs. T/F
Both are true
(Statement 1) There tends to be a strong gradient in air density from one side of a dryline to the other. (Statement 2) Drylines are common in the spring in the high plains region of the United States. T/F
Both are true
Which of the following helps lead to lower pressure: - Sinking air - Upper level divergence and low level convergence - Rising air - Upper level convergence and low level divergence - Both a and d - Both b and c
Both b and c
The net magnitude of vertical velocity over a forecast location depends upon: - The magnitude of lifting mechanisms - The magnitude of sinking mechanisms
Both the magnitude of lifting mechanisms & the magnitude of sinking mechanisms
(Statement 1) A forecast model will generally be more accurate if it gets more accurate initial data. (Statement 2) A forecast model will generally be more accurate if it gets a higher density of initial data. T/F
Both true
(Statement 1) A homogeneous ball has no natural top. (Statement 2) People often associate the direction of up with the direction that is opposite from the gravitational force at the location they are at. T/F
Both true
(Statement 1) Drylines generally advance forward during the day and retreat at night. (Statement 2) A dryline separates warm/dry air from warm/moist air. T/F
Both true
(Statement 1) Freezing rain is another term for sleet. (Statement 2) Snow will cool the air when it melts, evaporates and/or sublimates into the air. T/F
Both true
(Statement 1) The sublimational power of the sun on surface snow cover increases as the sun angle increases. (Statement 2) Ice can go straight from an ice to a vapor. This is called sublimation. T/F
Both true
Which of the following would most likely cause a fogging up on the inside of the windows in a car? - Decreasing relative humidity inside car due to turning on heater - Very humid air outside with the windows being colder than the air outside - Breathing out moisture that raises the relative humidity in the car to 100% - The air outside being the same temperature as the air in the car
Breathing out moisture that raises the relative humidity in the car to 100%
Why do bridges and over passes usually ice up before other roads? - Bridges and overpassess are more exposed to the air and thus cool more quickly - Surface frictional warming between tires and the road is less on bridges and overpasses - Bridges and overpasses tend to retain more heat - Bridges and overpasses are made of substances that tend to freeze more easily
Bridges and overpassess are more exposed to the air and thus cool more quickly
Which of the following would be most expected from an airmass thunderstorm? - Tornado - Brief heavy rain and gusty winds - Severe straight line winds - Large hail - Light rain that lasts for several hours
Brief heavy rain and gusty winds
Which of the following indicates the most cloud cover: - Fair - Broken - Mostly cloudy - Party cloudy
Broken
The mesolow from a thunderstorm develops due to: - Dense sinking air in the downdraft region - Buoyant rising air in the updraft region
Buoyant rising air in the updraft region
How can a radar operator best determine that a storm is "severe"?
By studying DbZ values, VILs, Radial velocities, and radar signatures such as bow echos
How can a forecaster tell the difference between ridging and an inverted trough? - By size - By amplitude - By elevation - By the direction of wind flow
By the direction of wind flow
A surface pressure of 980 mb would represent a benchmark value for: - Lowest pressure observed on earth's surface - Average sea level pressure - CAT 1 Hurricane or a very intense mid-latitude cyclone - Strong high pressure system
CAT 1 Hurricane or a very intense mid-latitude cyclone
The polar vortex in winter is most common over: - Mexico - Western U.S. - Central Canada - Gulf of Mexico
Central Canada
The pressure gradient is equal to: - Mass*acceleration - Force*distance - Change in pressure over change in distance - Energy per unit time
Change in pressure over change in distance
This air mass has the most dense air and thus tends to flow underneath other air masses when it interacts with them. - Continental tropical - Continental polar - Maritime polar - Maritime tropical
Continental polar
These clouds have some vertical development and are located in the upper levels of the atmosphere. The clouds have a lumpy appearance and are made of ice crystals. When viewed from the surface, each cloud element is about the size of a thumbnail.
Cirrocumulus
Which of the following statements is FALSE: - Cloud droplets freeze once temperature drops below 0 ° C. - The vapor pressure is higher over water than over ice - The typical raindrop is about 2 millimeters in diameter - Salt particles make good condensation nuclei
Cloud droplets freeze once temperature drops below 0 ° C.
Why do clouds float in the air instead of dropping to the surface from gravity? - Water vapor is more dense than diatomic Oxygen or diatomic Nitrogen - Clouds are less dense than the surrounding air - Air within clouds is negatively buoyant
Clouds are less dense than the surrounding air
All of the following are favorable for morning dew except: - Soil with a high moisture content - Cloudy skies - Light winds - Low afternoon dewpoint depression preceding the night
Cloudy skies
On a night with record low temperatures all of the following conditions are common except: - Snow on the ground or soil temperature well below normal - Light wind - Dry air - Cloudy skies
Cloudy skies
Which of the following air masses is the most dense?
Cold and dry
Which of the following is an example of cold thermal advection? - Cold front transporting cooler air into the forecast area - Radiation cooling at night - Evaporational cooling and causes the temperatures to fall - Cooling aloft produced by rising air - The cool wind of thunderstorm outflow
Cold front transporting cooler air into the forecast area
The California Current off the US West Coast is a ___________ ocean current while the Gulf Stream off the US East Coast is a ______________ ocean current. This helps lead to dry summers in California and relatively wet summers in the SE US.
Cold, Warm
Clear skies with good visibility occurs due to: - Sinking air - Low amounts of air pollution - Dry air
Combo of all options
Frozen dew occurs when: - Condensed water freezes - Deposition of water vapor to ice
Condensed water freezes
This is a term to describe a temperature lapse rate that is between the moist and dry adiabatic lapse rate. - Convective instability - Potential instability - Conditional instability - Latent instability
Conditional instability
In which air mass type would a rising parcel's slope at the moist adiabatic lapse rate be closest to the dry adiabatic lapse rate? The moist adiabatic lapse rate is NOT a constant. The moist adiabatic lapse rate has a smaller slope than the dry adiabatic lapse rate if a parcel contains moisture. The amount of latent heat release depends on the temperature and moisture content of the air. - Maritime tropical (warm and moist) - Maritime polar (cool moist) - Continental tropical (hot and dry) - Continental polar (cold and dry)
Continental polar (cold and dry)
For cloud bases to occur at this level, the boundary layer temperature must first warm to the convective temperature. - Convective Condensation Level - Lifted Condensation Level
Convective Condensation Level
The ______________ is the height of cloud bases resulting from air rising from the surface due to positive buoyancy alone. - Lifted Index - Lifted Condensation Level - Convective Condensation Level - Level of the Free Convection
Convective Condensation Level
This is the amount of energy per mass a parcel of lifted surface air must overcome in order to lift into the region of positive instability. - Convective Inhibition - Convective Available Potential Energy - Lifted Index - Lifted Condensation Energy
Convective Inhibition
This is an instability increase caused by an increase of dewpoints within the troposphere especially in the lower troposphere. - Convective Instability of the First Kind - Convective Instability of the Second Kind
Convective Instability of the Second Kind
A thermal trough at the surface is a region with relatively: - Warmer temperatures - Cooler temperatures - Higher dewpoints - Lower dewpoints
Cooler temperatures
Surface snow cover has a ____________ effect of high and low temperatures especially when skies are clear. - Warming - Cooling
Cooling
All contribute to producing a low level capping inversion that can prevent thunderstorm development EXCEPT: - Sinking air aloft - Warm air advection aloft - Significant cooling of the earth's surface - Cooling aloft produced by strong uplift
Cooling aloft produced by strong uplift
The geostrophic wind is a balance of the pressure gradient force and the _______________ force. This balance causes air to flow nearly parallel to the height contours in the mid and upper levels of the atmosphere.
Coriolis
A COL will produce: - Frontogenesis - Frontolysis - Could be frontogenesis or frontolysis depending on the orientation of high and low pressure systems
Could be frontogenesis or frontolysis depending on the orientation of high and low pressure systems
When viewed from above the North Pole of the Earth, the earth rotates _________________ and makes a complete turn in 24 hours. This causes low pressure to spin counterclockwise in the Northern Hemisphere. Clue: the sun rises in the east and sets in the west.
Counterclockwise
Positive vorticity is a ______________ spin to the air in the Northern Hemisphere. - Cyclonic (counterclockwise) - Anticyclonic (clockwise) - Convective - Retrograde
Cyclonic (counterclockwise)
Which of the following is NOT a primary "control" of climate? - Altitude - Daily weather - Latitude - Ocean currents
Daily Weather
Greater overnight cooling will occur when the boundary layer: - Decouples - Does not decouple
Decouples
The relative humidity will ___________ when the temperature increases while the dewpoint remains constant.
Decrease
When air rises the relative humidity of the air will increase and the dewpoint depression of the air will _________.
Decrease
The maximum unambiguous range will increase if the pulse repetition frequency of the radar ____________.
Decreases
The Lifted Index is made more unstable by: - Decreasing 500 millibar temperature - Decreasing surface temperature - Decrease surface dewpoint
Decreasing 500 millibar temperature
All of the following will exacerbate the flash flood potential except: - Snow melt - Dense vegetation - Saturated soil - Training of thunderstorms
Dense vegetation
In a _____________, severe winds encompass a distance of at least 400 km (250 miles) either out ahead of or along a squall line MCS. - Tornado - Tropical storm - Derecho - Downdraft
Derecho
Surface temperature will still warm on a cloudy barotropic day because: - Evaporational cooling occurs - Diffuse solar radiation reaches the surface - The air is rising - Water vapor is a greenhouse gas
Diffuse solar radiation reaches the surface
Velocity multiplied by time is ______________.
Distance
A type B mid-latitude cyclone has its genesis in the upper levels of the atmosphere and builds toward the surface. Which of the following synoptic scale features most heavily influences the development of type B cyclones?
Divergence created by meridional flow within the jet stream
Where is the lion's den? - Downdraft region of a severe thunderstorm - Inside the eyewall of a hurricane - Precipitation that wraps around a mesocyclone - The region with blizzard conditions in association with a low pressure system
Downdraft region of a severe thunderstorm
Cold air advection plus ____________ will maximize the amount of cooling that takes place. - Solar radiation - A warm ground temperature - Evaporational cooling - Sinking air
Evaporational cooling
To estimate the afternoon high on a morning sounding, take the environmental temperature 150 millibars above the surface and bring the parcel down _________ to the surface and read off the new temperature. This method while quick and practical does have many pitfalls.
Dry adiabatically
All of the following will strengthen a mid-latitude cyclone except: - Dry air advection into the cyclone - Moist air advection into the cyclone - Strengthening upper level divergence - Strengthening low level convergence
Dry air advection into the cyclone
This is a synoptic scale boundary that separates maritime tropical (mT) air from continental tropical (cT) air. Dewpoint changes dramatically from one side of the boundary to the other. Severe thunderstorms can occur along this boundary, especially in Spring and early Summer.
Dryline
If the earth was tilted by 90 degrees, which of the following would be most true? - Each pole would directly face the sun twice per year - Both poles would be very hot or very cold at the same time - The sun would always rise in the east and set in the west when viewed from Earth - Each pole would alternate between 3 months of light and dark
Each pole would directly face the sun twice per year
______________ is the vertical height above the surface to the target at which the radar beam intersects the target. - Elevation angle - Azimuth - Range - Echo height
Echo height
Instability release in a thundersnow situation usually occurs from: - Surface based convection - Dynamic lifting - Fronts - Elevated convection
Elevated convection
TEI (THETA-E INDEX) assesses the potential for _____________________. - Elevated convection - Freezing temperatures - Severe weather - Tropical convection
Elevated convection
When forecasting large hail, what are the primary thermodynamic ingredients to look for that produce large hail?
Elevation, CAPE and freezing level
Which of the following is shown on satellite images with respect to a severe thunderstorm: - TVS - Elevated reflectivity - V-notch - Enhanced-V
Enhanced-V
All the following enhance the lightning potential in a storm except: - High Precipitable Water - Large instability - Entire troposphere below freezing - Strong wind shear
Entire troposphere below freezing
The pressure level at the top of the CAPE region is the: - Level of Free Convection - Lifted Condensation Level - Equilibrium Level - Convective Condensation Level
Equilibrium Level
Which of the following processes ABSORBS the most latent heat? - Melting - Evaporation - Freezing - Condensation
Evaporation
As a cold front presses equatorward the air behind the cold front will generally warm over time. All the following will help support this except: - Higher sun angles - Warm soils - Depth of cold air becoming more shallow - Evaporation into cold and dry air
Evaporation into cold and dry air
The maximum unambiguous velocity will increase if the pulse repetition frequency of the radar ____________.
Increases
The sound of thunder is produced by: - Flashes of light energy - Expansion and contraction of air - Clouds rubbing each other - Release of atomic energy through fusion
Expansion and contraction of air
To make a storm as severe as possible and you can pick three ingredients, of the four choices below which you would you not pick? - Extreme instability - Strong speed and directional wind shear - Strong dynamic lifting of saturated warm air - Extremely high value of Precipitable Water and saturated air throughout the troposphere
Extremely high value of Precipitable Water and saturated air throughout the troposphere
What is a heat burst?
Extremely hot and dry downdraft of air
Which of the following is true during an eyewall replacement cycle: - Maximum sustained wind speeds tend to increase in the eyewall - A smaller eye expands outward and replaces a larger eye - The core of strongest wind tends to become more compact - Eyewall replacement cycles are common when a hurricane reaches CAT 5 status
Eyewall replacement cycles are common when a hurricane reaches CAT 5 status
The temperature and dewpoint can not be negative on the Fahrenheit temperature scale. T/F
False
Increasing the wind speed causes the temperature of the air to decrease. - True - False
False - this one may have been on my NWA test
What is the feature at "D"? - Flanking line - Mammatus - Anvil - Outflow boundary
Flanking line
For which significant storm event are high values of Precipitable Water compared to climatological normal often needed. - Strong convective wind gusts - Flash flooding - Tornadoes - Large hail
Flash flooding
All are characteristics of a shower expect? - Off and on precipitation - Brief precipitation - Quick beginning and quick ending - Flooding rain
Flooding rain
The two weather disasters that result in the greatest loss of life are:
Floods and Lightning
Why are thunderstorms less common in California than Florida?
Florida has warmer ocean waters surrounding it. This results in higher dewpoints, instability and thus more thunderstorms.
The SWEAT index takes into consideration directly or indirectly all of the following except: - Wind shear - Moisture - Forced lifting - Instability
Forced lifting
What is the feature at "H" on the right side of the diagram? - Forward Flank Downdraft - Rear Flank Downdraft
Forward Flank Downdraft
The temperature has been below freezing all night. The next morning the car has clear ice and icicles on it. This ice was caused by: - Frozen dew - White frost - Freezing rain (drizzle) - Could be any of the above
Freezing rain (drizzle)
Which of the following has the highest albedo and thus more reflected solar radiation? - Fresh snow - Water - Grass - Blacktop
Fresh Snow
Which of the following has the highest albedo? - Fresh snow - Old or dirty ice - Water with sun directly overhead - Blacktop
Fresh snow
Noises from the wind are caused by: - Friction - Thermal expansion - Molecular energy - Mass
Friction
This force causes the wind to slow down, causes air to converge into surface low pressure, and causes wind to be turbulent (gusty) near the surface. - Coriolis - Pressure Gradient Force - Friction - Gravity
Friction
This is the retarding force that is responsible for air converging into low pressure systems in the boundary layer: - Upward vertical velocity - Gravity - Friction
Friction
The mid-latitude winds in the Northern and Southern Hemispheres flow generally from which direction?
From the west in both hemispheres
This is the term for liquid condensation on the ground that then freezes during the course of the night: - Dew - Frost - Frozen dew - Freezing rain
Frozen dew
A "tornadic circulation" that is not in contact with the ground is termed a __________. If the circulation is not in contact with the ground then it is not a tornado. - Breeze - Gust front - Funnel - Vort max
Funnel
This is a forecast model used to help develop 3 to 10 day forecasts: - ETA - NGM - AVN - GFS
GFS
The freezing of water at the top of a cumulonimbus updraft is termed: - White-out - Glaciation - Blizzard top - Avalanche
Glaciation
All of the following usually significantly restrict the viewing of a tornado except: - Tall trees - Good preexisting visibility - Night - Heavy rain
Good preexisting visibility
What is a meteogram: - Graph showing wind direction and wind speed with height - A temperature and dewpoint sounding of the troposphere - Graphical model output of various forecasted parameters - A forecasting tool to help predict snowfall
Graphical model output of various forecasted parameters
The primary moisture source for severe thunderstorms in the Great Plains originates from the:
Gulf of Mexico
The inflow notch on this supercell type resembles a kidney bean: - Classic - LP - HP
HP
These supercell types have high PW and have tornadoes that are difficult to see in the field: - LP - Classic - HP - Super
HP
VIL can be used to forecast the threat for: - High winds - Tornadoes - Icing - Hail and heavy rain
Hail and heavy rain
Which of the following weather parameters is used in classifying if a thunderstorm is severe? - Hail size - Lightning intensity - Rain intensity
Hail size
If a lightning strike is a sufficient distance from the observer, sound from the strike will not be heard. These silent bolts are called ______________ lightning.
Heat
Water has a ___________ heat capacity. This means a large amount of energy is needed to raise the temperature of water relative to other substances.
High
Mercury is used in liquid-in-glass barometers because it has this property: - High density - Low density - Clear color - Flowing nature
High density
Fresh snow cover tends to cause the:
High temperature to be cooler than it otherwise would be and the low temperature to be cooler than it otherwise would be
As an object emits sound or light and moves TOWARD you, the frequency of the sound or radiation will be _______________ relative to you than the moving object. This is the Doppler effect.
Higher
The rule of thumb is that the __________ the echo tops are in a storm then the stronger the updraft is that produced that storm. - Larger - Smaller - Higher - Lower
Higher
Significant vorticity advection will always occur when ___________________________________.
Higher values of vorticity are quickly advected into a forecast area
This feature on radar reflectivity is an indication a tornado may be present: - High reflectivity core - Gate to gate shear - Hail spike - Hook echo
Hook echo
The flow from high to low pressure is caused by the: - Coriolis force - Frictional force - Gravitational force - Centripetal force - Pressure Gradient force
Pressure Gradient force
The 3-H's for the summer-like conditions in the Southeast U.S. are hot, hazy and:
Humid
A rapid decrease in dewpoint with height is termed a(n): - Hydrolapse - Inversion - Moist layer - Isothermal layer
Hydrolapse
This is a fog composed of ice crystals: - Freezing fog - Ice fog - Advection fog - Radiation fog
Ice fog
When examining the reflectivities within a storm with radar, usually the highest reflectivities will be: - In the upper levels of the storm - In the middle levels of the storm - In the lower levels of the storm
In the middle levels of the storm
On a clear barotropic day, the greatest temperature increase tends to occur________________________.
In the morning hours
In which location are hurricanes most likely to develop? - In warm tropical waters 10 ° to 25 ° North and South of equator - Along the equator over continental locations - Along the west coast of continents at 35 ° North or South - In either the Mediterranean Sea, off the east coast of South America, or just south of Australia
In warm tropical waters 10 ° to 25 ° North and South of equator
Coastal upwelling, the Gulf Stream and cloud top temperatures are best determined using:
Infrared imagery
Which imagery uses enhancements to display important temperature details of thunderstorms and hurricanes?
Infrared imagery
An environment in which parcels of lifted air can rise on their own due to positive buoyancy through a region of CAPE is termed an environment with: - A temperature increase with height - Instability - Severe weather potential - Strong shear
Instability
The difference between stratiform and convective precipitation is: - Instability release - Forced lifting - Warm moist air in the lower troposphere - Wind shear
Instability release
The estimation of a meteorological value such as temperature between two known data points is termed: - Extrapolation - Boundary error - Omega - Interpolation
Interpolation
A very dry PBL with high relative humidity air in the middle troposphere is termed a(n) ________ sounding. - Inverted-V - Loaded gun - Unstable - Convectively unstable
Inverted-V
Contours of surface pressure change are termed: - Height change contours - Isobars - Isohypses - Isallobars
Isallobars
The movement of less dense air on the synoptic scale over more dense air at a gradual slant that increases in elevation as the air advects is related to: - Cold Air Advection - Positive Vorticity Advection - Orographic lifting - Isentropic lifting
Isentropic lifting
All the following isopleths will have an S-shaped over the region a strong mid-latitude cyclones influences except: - Isobars - Thickness lines - Isotherms - Isodrosotherms
Isobars
These connects points of equal barometric pressure normalized to sea level. - Isobars - Isohypses - Isohyets - Isotachs
Isobars
A contour line of equal rainfall is called an: - Isotach - Isobar - Isohyet - Isohypse
Isohyet
How can virga cause the atmosphere to become increasingly unstable?
It can cool the mid-levels of the atmosphere
Which of the following is true of a "capping inversion"? - It can prevent thunderstorms from developing - It can enhance thunderstorm activity due to heat and moisture buildup in the planetary boundary layer - It is a rapid temperature decrease with height above the planetary boundary layer
It can prevent thunderstorms from developing AND It can enhance thunderstorm activity due to heat and moisture buildup in the planetary boundary layer
Which of the following best explains how pressure decreases with height in the Earth's atmosphere? - It decreases at a constant rate (linear decrease) - It decrease quickly at first then more gradually (exponential decrease) - It decreases at a rate of 9.8 millibars per kilometer - It decreases in the troposphere, increases in the stratosphere, then decreases to the top of the atmosphere
It decrease quickly at first then more gradually (exponential decrease)
An astronaut on the moon fills a balloon with helium. He then walks on the moon's surface holding the balloon in his hand. He then lets go of the balloon. What happens to the balloon? - It rises - It falls to the moon's surface - It remains suspended at the same height he let it go
It falls to the moon's surface
Which of the following is true of a continental polar air mass? - It has a high degree of stability - The relative humidity is generally high - The source region is over cold ocean water - Precipitation tends to be heavy within the air mass
It has a high degree of stability
What is a trigger mechanism? - It is a process that prevents precipitation or storms from occurring - It is a sounding that has a region of positive CAPE - It is any process that initiates precipitation or storm development - It is in reference to Omega forcing from either low level divergence or upper level convergence
It is any process that initiates precipitation or storm development
Why is the Wet Adiabatic Lapse Rate not a constant on the Skew-T Log-P diagram? - Latent heat absorption from evaporational cooling - Solar radiation warming - The melting of liquid water drops - Latent heat release from condensation
Latent heat release from condensation
For locations at a constant elevation, the most important global climatic control to expected temperatures is: - Ocean currents - Proximity to an ocean body - Latitude - Prevailing wind
Latitude
Climate is a function of:
Latitude, Altitude, Continentality & Ocean currents
Which of the following reasons explains why ice crystals develop much more rapidly than liquid water drops in the upper and middle levels of thunderstorms? - When temperatures drop below freezing, condensation of water vapor onto liquid water does not take place. The water vapor can, however, build on ice crystals due to deposition. - Electrical currents within thunderstorms allow the building of water vapor on ice crystals more rapidly than on liquid water drops. - It is because the vapor pressure of ice is less than that over water. This produces a vapor pressure gradient between liquid and frozen water. This causes water vapor to move from liquid water drops toward ice crystals. - It is due to the turbulent motion of air. Condensation rates onto liquid water slow with increasing windspeed.
It is because the vapor pressure of ice is less than that over water. This produces a vapor pressure gradient between liquid and frozen water. This causes water vapor to move from liquid water drops toward ice crystals.
What is elevated convection? - It is any CAPE that is released in the troposphere - It is a thunderstorm that develops at the jet stream level - It is convection that has an enhanced chance of being severe - It is convection not resulting from PBL based convection
It is convection not resulting from PBL based convection
The term "elevated convection" refers to:
It is convection that has an origin above the planetary boundary layer
What is vorticity?
It is cyclonic or anticyclonic rotation which can be used to assess upper level divergence
Which of the following is true concerning 700 mb synoptic scale vertical velocity: - Downward vertical velocity guarantees storms will not occur - Upward vertical velocity guarantees storms will occur - It is used to determine how strong the updraft within a storm will be - It is the compilation of all upward and downward synoptic forcing mechanisms over an area
It is the compilation of all upward and downward synoptic forcing mechanisms over an area
Sunny days can be very cold because: - Higher sun angles are less efficient in warming the earth's surface - The daylight hours are more in the winter - The sun can not warm the air either directly or indirectly - It takes solar energy time to modify very cold air and also low sun angles are not efficient at warming the air
It takes solar energy time to modify very cold air and also low sun angles are not efficient at warming the air
Which of the following states has the most frequent and largest hail of the four choices below? Why? - Kansas; many high CAPE days, freezing levels can be relatively low - Florida; large number of thunderstorm days - Michigan; high latitude, lake effect hail, many summer storms - Oregon; orographic lifting, many thunderstorm days, jet stream
Kansas; many high CAPE days, freezing levels can be relatively low
These are the three hurricanes in 2005 what were CAT 5 while in the Gulf and each struck the U.S. Gulf coast: - Katrina, Rita, Wilma - Andrew, Camille, Katrina - Danny, Katrina, Wilma - Bob, Donna, Stacy
Katrina, Rita, Wilma
Which of the following temperature scales is a RATIO temperature scale? A ratio is the most powerful mathematical tool in statistics.
Kelvin Scale
Which of the following is not a part of the Omega Equation? - Differential Vorticity Advection - Land cover and soil moisture boundaries - Thermal Advection
Land cover and soil moisture boundaries
What time of the day are thunderstorms generally most common: - Early morning - Around midnight - Around noon - Late afternoon
Late afternoon
The ______________ is the time of the year most relevant for the use of the term Indian summer. - Early spring - Middle and late summer - Late fall
Late fall
Fog tends to be thicker and more common in: - Rural areas - Urban areas
Rural areas
This method examines individual layers of the troposphere and assess the stability classification, wind and moisture characteristics of that layer. - Bubble method - Bulk measure method - Layer slice method - Omega method
Layer slice method
If a jet streak is on the ____________ side of a trough, the trough will deepen and become more amplified.
Left
The average atomic weight of air is 28.97 atomic units. Water vapor has an atomic weight that is __________ than this value, thus when water vapor is added to the air it makes the air less dense.
Less
As more precision in time and space for a forecast is required below the synoptic scale, forecast models tend to become: - More accurate - Less accurate
Less accurate
The reflectivity from dry ice is ______ than the reflectivity for wet ice that is the same size. - More than - Less than
Less than
The pressure level at the bottom of the CAPE region is the: - Level of Free Convection - Lifted Condensation Level - Equilibrium Level - Convective Condensation Level
Level of Free Convection
The pressure level at which air becomes saturated when forced lifting from the PBL occurs is termed the: - Convective Condensation Level - Equilibrium Level - Lifted Condensation Level - Maximum Parcel Level
Lifted Condensation Level
Which of the following will always be highest in elevation?: - Level of Free Convection - Equilibrium Level - Maximum Parcel Level - Lifted Condensation Level
Lifted Condensation Level
All of the following are factors that reduce the chance of a tornado except: - Weak wind shear - Lifted Condensation Level close to the earth's surface - Low instability - Weak PBL wind
Lifted Condensation Level close to the earth's surface
Clear air mode is often used to locate: - Tornadoes - Hail - Heavy rain - Light snow
Light snow
What contributes to forming giant snow flakes? - Strong wind, light precipitation, wet snow - Light wind, heavy precipitation, wet snow - Strong wind, heavy precipitation, dry snow - Light wind, heavy precipitation, dry snow
Light wind, heavy precipitation, wet snow
The "dog days of summer" have the origin from the sun: - Causing outdoor dogs to suffer in the heat - Lining up with the star Sirius to produce hot weather - Allowing you and your friends to do outdoor activities - Causing severe thunderstorms due to the instability
Lining up with the star Sirius to produce hot weather
Four locations have a temperature of 70 F at 4 pm. Assuming the weather is the same for each location over night (clear skies, light winds) except dewpoint. Which location should have the cooler overnight low? - Location 1 (4 pm dewpoint of 65 F) - Location 2 (4 pm dewpoint of 60 F) - Location 3 (4 pm dewpoint of 55 F) - Location 4 (4 pm dewpoint of 50 F)
Location 4 (4 pm dewpoint of 50 F)
Which weather phenomena would be nearly impossible to observe without the aid of satellite imagery? - Location of a mid-latitude cyclone - Location of a cold front boundary - Location of a MCC - Location of a deep ocean hurricane
Location of a deep ocean hurricane
The Low pressure "L" on a surface map stands for: - Happy weather - Cold weather - Warm weather - Lousy weather
Lousy weather ---- ummm really?????
All are reasons that polar areas are cold except: - Low sun angle - Low amounts of water vapor - Low albedo - Low amount of daylight hours in cool season
Low albedo
For regions in the middle and high latitudes, the relative humidity inside a house tends to be much _________ in winter as compared to summer.
Lower
If you stand with your back to the wind and rotate to the right 30 °, the surface pressure will be _____________ to your left than your right.
Lower
Which of the following should be kept in mind when forecasting winter precipitation? - Make sure precipitation falls at the time the temperature profile supports winter precipitation - Make sure the surface dewpoint is at least 55 F - Make sure these is adequate instability, lift, and wind shear
Make sure precipitation falls at the time the temperature profile supports winter precipitation
What is the feature at "C"? - Downdraft - Mammatus - Anvil - Tornado
Mammatus
This air mass has abundant moisture and warm air: - Maritime Polar - Maritime Tropical - Continental Tropical - Continental Polar
Maritime Tropical
A dryline separates these two air masses: - Continental polar from maritime tropical - Maritime polar from maritime tropical - Maritime tropical and continental tropical - Continental polar from continental tropical
Maritime tropical and continental tropical
This is the pressure level that a previously convectively rising parcel of air stops rising: - Level of Free Convection - Equilibrium Level - Maximum Parcel Level - Lifted Condensation Level
Maximum Parcel Level
With an omega block over the region ____________ flow would be expected. - Zonal - Meridional
Meridional
The units of both CAPE and HELICITY ARE: - Meters per second squared - Joules - Newtons - Meters squared per seconds squared
Meters squared per seconds squared
Which of the following is a limitation of using the 850-mb temperature and bringing it down dry adiabatically to the surface to estimate the high temperature? - Method only works on cloudy days - Method does not work when fronts are passing through - Method only works for high elevation regions - Method does not work in the spring
Method does not work when fronts are passing through
All of the following further increase instability except: - Lower tropospheric warm air advection - Lower troposphere moisture advection - Middle and upper tropospheric warm air advection - Middle and upper tropospheric cold air advection
Middle and upper tropospheric warm air advection
What is one way in which a cloud erodes: - Cool the temperature within the cloud - Cause the air to rise within the cloud - Mix environmental air into the cloud - Increase the thickness of the cloud
Mix environmental air into the cloud
Why do urban temperatures tend to be warmer than rural temperatures on sunny light wind days? - More sensible heat release in urban areas - Less greenhouse gases in urban areas - More moisture and trees in urban areas - Higher elevation in urban areas
More sensible heat release in urban areas
Outflow boundaries are miniature cold fronts that form due to the presence of: - Positive vorticity advection - Warm air advection - Coastlines - Multi-cell thunderstorms
Multi-cell thunderstorms
A storm moving from 225 degrees is moving from the: - Northeast - Southeast - Northwest - Southwest
Southwest
When a superadiabatic lapse rate occurs, it most commonly occurs: - Near the surface - At the top of the boundary layer - Near the 500 mb pressure surface - Within the tropopause
Near the surface
El Nino occurs when the SOI is _____________ for an extended period of time. - Positive - Negative
Negative
The eastern U.S. tends to have more snow storms and colder weather when the NAO is: - Positive - Negative
Negative
This tilt of an upper level trough on a pressure surface is associated with an enhanced chance of severe weather when cold dry air swings over the top of warm and moist air. - Positive tilted trough - Neutrally tilted trough - Negatively titled trough
Negatively titled trough
The dewpoint is greater than the temperature:
Never
The most abundant gas in the atmosphere by volume is _________. This gas comprises 78% of the Earth atmosphere by volume.
Nitrogen
A low pressure system is located over Colorado. Upslope flow would be expected: - North of Colorado - South of Colorado
North of Colorado
A surface low pressure system is located directly south of you while a surface high pressure system is located directly north of you. The expected surface wind direction is from the __________.
Northeast
Tornado watches are routinely issued for this quadrant of a hurricane: - Northeast - Southeast - Northwest - Northeast
Northeast
A hurricane is moving toward the west and directly toward central Florida. Which portion of Florida should expect the greatest storm surge and highest wind? - Northern Florida coast Southern Florida coast
Northern Florida coast
A strong developing mid-latitude cyclone over the United States generally tilts to the _______________ with height. They tilt toward the cold air.
Northwest
The shape of Earth is a(n): - Oblate spheroid - Perfect sphere - Eroded square - Apple shape
Oblate spheroid
When one front lifts another front it is termed a(n) _____________ front on a surface chart. - Occluded - Stationary - Kata - Barotropic
Occluded
A(n) ___________ surface such as rock does not allow light to penetrate while a __________ surface does allow some light to transmit.
Opaque, transluscent
Where is the bear's cage? - Downdraft region of a severe thunderstorm - Inside the eyewall of a hurricane - Precipitation that wraps around a mesocyclone - The region with blizzard conditions in association with a low pressure system
Precipitation that wraps around a mesocyclone
All the following processes will increase the lower tropospheric relative humidity except: - Lifting of air - Evaporation of precipitation - Orographic descent - Advection of air with a much lower dewpoint depression
Orographic descent
When strong Cold Air Advection occurs at 850 mb during the day time there is a tendency for the high temperature predicted by the forecast models to be: - Overestimated - Underestimated
Overestimated
What is the feature at "B"? - Flanking line - Overshooting top - Anvil - Outflow boundary
Overshooting top
When forecasting large and damaging tornadoes, what are the primary thermodynamic ingredients to look for?
PBL direction wind shear, mid-level moisture, speed shear, CAPE, weak to moderate cap and PBL moisture
The two variables that meteorologists examine on the MOS to forecast precipitation are: - Cloud cover and dewpoint - Dewpoint and ceiling - POZ and OBV - POP and QPF
POP and QPF
The thermal wind tends to be orientated: - Parallel to the 500 mb height contours and 1000 to 500 mb thickness lines - Perpendicular to the 500 mb height contours and 1000 to 500 mb thickness lines
Parallel to the 500 mb height contours and 1000 to 500 mb thickness lines
The smallest element on a satellite image is called a(n):
Pixel
All of the following will lead to the development of an inversion except: - WAA vertically above CAA - Radiational cooling of the earth's surface at night - Middle troposphere subsidence - Polar air flowing over the much warmer Great Lakes
Polar air flowing over the much warmer Great Lakes
The 5,400 meter 1000 to 500 mb thickness generally separates: - Arctic air from Polar air - Tropical air from Mid-latitude air - Polar air from Mid-latitude air - Equatorial air from tropical air
Polar air from Mid-latitude air
The eastern U.S. tends to be warmer when the AO is: - Positive - Negative
Positive
In MOST cloud to ground lightning strikes, the ground tends to be _______________ charged.
Positively
This is the amount of moisture that would accumulate on the earth's surface if all water vapor aloft was condensed onto the earth's surface and measured. - Mixing ratio - Dewpoint - Precipitation accumulation - Precipitable Water
Precipitable Water
Precipitable Water is an important factor in determining whether a supercell will be HP, Classic or LP. T/F
Precipitable Water is an important factor in determining whether a supercell will be HP, Classic or LP
An isobar is a line of constant ________________.
Pressure
The typical wind direction that a location has for a certain time of the year is called the _____________ wind. When the wind is from the prevailing direction then the weather is generally typical. When the wind shifts away from the prevailing direction then it often indicates atypical or changing weather.
Prevailing
What causes advection fog? - Produced when very cold air moves over a body of water - Produced when air that is warmer and more moist than the ground surface moves over the ground surface - Produced when clear skies and light winds allow the temperature to cool to the dewpoint - Produced when air flows upslope into higher elevations regions and fog develops
Produced when air that is warmer and more moist than the ground surface moves over the ground surface
A thunderstorm complex releases energy measured in the ___________ of Joules. - Millions - Billions - Trillions - Quadrillions
Quadrillions
CAPE and LI can be determined from all of the following sources except: - Radar - Satellite - Rawinsonde - Dropsonde
Radar
The motion toward or away from radar is ______________.
Radial motion
This is the type of fog that forms on nights with light wind, clear skies, low dewpoint depressions, and moist soils.
Radiational fog
Which of the following is a diabatic process as compared to an adiabatic process? - Convection - Orographic lifting - Radiational heating or cooling - Rising air due to PBL convergence
Radiational heating or cooling
A precipitation rate of 0.15 inches per hour of rain is: - Light rain - Rain - Heavy rain
Rain
What is the feature at "E"? - Rear Flank Downdraft - Wall cloud - Rain / Hail core - Forward Flank Downdraft
Rain / Hail core
What is the feature at "G"? - Rain Free Base - Wall cloud - Rain / Hail core - Forward Flank Downdraft
Rain Free Base
All of the following generally promote larger hail except: - Increase of CAPE - Raising of freezing level - Convective instability (through further drying of middle troposphere and warm and humid air in the lower troposphere) - Increase of elevation above sea level
Raising of freezing level
On a NEXRAD velocity display, air moving away from the radar site will most likely be given a color of:
Red
How is the center of a tropical system determined? - Region with strongest convection - Region with lowest pressure - Region with highest wind speed - Region with highest storm surge
Region with lowest pressure
Which of the following is NOT displayed on the ETA, MRF and NGM surface pressure chart? - Thickness - Sea level pressure - Relative humidity - Forecasted precipitation total
Relative humidity
When an ice cube is freezing, instead of cooling, the ice cube: - Warms - Remains at a constant temperature - Condenses - Evaporates
Remains at a constant temperature
In this blocking pattern air swoops around a ridge and then around a trough. This results in the air taking a backward-S trajectory and making limited west to east movement. - Omega block - Ring of fire - Rex block - Cut-off low
Rex block
Rising motion due to vorticity and warm air advection are most commonly found to the ____________ of the 500 millibar trough axis over the United States.
Right
Which of the following statements is false concerning orographic lifting? - Rising air cools - Rising air decreases in relative humidity - Other terms for orographic lifting are upslope flow and topographic uplift - Orographic lifting can lead to clouds and precipitation
Rising air decreases in relative humidity
If the earth was not tilted, which of the following would be most true?: - Equatorial regions would be much hotter - Polar regions would be much colder - Seasonal changes would be small - Winters would be colder and summers would be hotter
Seasonal changes would be small
The ___________ night after a cold front passage tends to be colder. This is because the winds tend to be lighter the second night, skies tend to be clear and most of the Cold Air Advection has occurred by that point.
Second
The autumnal equinox occurs on: - September 23 - December 23 - March 23 - June 23
September 23
An outflow boundary is an example of a: - Warm front - Cold front - Shear axis - Dryline
Shear axis
An example of a source region of continental arctic (cA) air is: - Mexican plateau - Gulf of Alaska - Northern Great Plains of U.S. - Siberia
Siberia
When the temperature is below freezing from the surface to 500 millibars, what precipitation type would you expect?
Snow
The "bright band" on radar imagery forms due to:
Snow melting before it reaches the surface
Snowflakes generally take longer to reach the surface than raindrops during descent because: - Snowflakes are more dense - Snowflakes are smaller - Snowflakes are easily wafted by the wind - Snowflakes are heavier
Snowflakes are easily wafted by the wind
Which of the following processes will result in a GREATER dewpoint depression at the surface? The dewpoint depression is the difference between the temperature and the dewpoint. - Wet-bulb cooling - Saturating previously unsaturated air - Radiational cooling - Solar heating
Solar heating
The measure of turbulence within a radar data pixel is termed: - Spectrum width - Vorticity - Rotation - Aliasing
Spectrum width
This term is defined as a measure of dispersion of velocities within the radar sample volume. It can be used to detect a tornado vortex signature since velocities will have various directions within a range gate.
Spectrum width
A moisture tongue will likely have all of the following associated with it except: - Warm air advection - Higher dewpoints - Strong wind - Stability
Stability
If the weather is uncomfortable warm, which of the following will help it feel cooler: - Increasing the dewpoint - Step into direct sunlight - Stand in the shade in a breezy area and spray water mist on your face - Exercise
Stand in the shade in a breezy area and spray water mist on your face
(Statement 1) Ocean temperatures tend to be highest climatologically in late summer. (Statement 2) The sun is at the highest noon solar elevation (maximum insolation) in early summer. T/F
Statement 1 and Statement 2 are both true
Statement 1) As temperatures warm, increasing amounts of water vapor can be added to the air. (Statement 2) The maximum amount of water vapor that can be in the air is a function of temperature. T/F
Statement 1 and Statement 2 are both true
How does "edge definition" differ between Stratus and Cumulus clouds? This applies to when these clouds are seen in person also.
Stratus have a low edge definition while cumulus have a well defined definition
Which of the following defines the "low level jet"? - Gust front winds associated with severe thunderstorms - Strong PBL winds in the Great Plains which rapidly draws warm and moist air from the Gulf of Mexico - It is a polar or subtropical jet stream which is at an unusually low pressure level - It is the contrails produced by jet aircraft
Strong PBL winds in the Great Plains which rapidly draws warm and moist air from the Gulf of Mexico
A strong bowing reflectivity gradient is indicative of: - Strong convective wind gusts - Large hail - Strong tornadoes - Snow
Strong convective wind gusts
Which of the following would most likely cause a trough to become negatively tilted? - Strong warm air advection in the lower troposphere - Upper level convergence aloft - Strong jet streak rounding the base of a trough - Strong thunderstorm updrafts
Strong jet streak rounding the base of a trough
Which of the following is NOT conducive to lake effect snow? - Continental polar air advecting over warm Great Lake waters - Strong vertical directional and speed shear with positive LI's - Orographic lifting and frictional convergence - Large temperature difference between lake and overriding cP air
Strong vertical directional and speed shear with positive LI's
The 850 to 700 mb layer thickness can increase by which of the following processes?
Strong warm air advection into the layer
A bow echo is produced by: - Storms developing along a cold front - A line of storms encountering abundant moisture - Strong winds aloft entering the backing side of a squall line - The merging of two supercells
Strong winds aloft entering the backing side of a squall line
An inversion will promote: - Subrefraction - Normal refraction - Superrefraction - No refraction
Superrefraction
If the radar indicates a storm top is at 50,000 feet and the actual storm top is at 44,000 feet, then _____________ occured. - Superrefraction - Subrefraction
Superrefraction
When the downward bending of radar waves is stronger than normal, such as in association with a strong temperature inversion, it is called ducting or can also be called _________________.
Superrefraction
For a lifting mechanism, where in the troposphere does a forecaster look for convergence to occur? - Surface, boundary layer and lower troposphere - Around the 500 mb level - In the upper troposphere
Surface, boundary layer and lower troposphere
When the air is unsaturated at a constant pressure, which value will always be greater: - Temperature - Dewpoint - Wet-bulb - Frost point
Temperature
Which of the following is analyzed on a lower tropospheric analysis: - Differential vorticity advection - Temperature advection - Jet stream - Longwave troughs and ridges
Temperature advection
Theta-E will increase as: - Wind speeds become stronger - Dynamic lifting becomes stronger - Temperature and dewpoint increase - Cloud cover increases
Temperature and dewpoint increase
What is an isothermal layer? - Temperature increase with height - Temperature decrease with height - Temperature fluctuation with height - Temperature constant with height
Temperature constant with height
If the relative humidity decreases it could be due to: - Temperature decreasing or dewpoint decreasing - Temperature increasing or dewpoint increasing - Temperature decreasing or dewpoint increasing - Temperature increasing or dewpoint decreasing
Temperature increasing or dewpoint decreasing
When is ducting most likely?
Temperature rapidly increases with height and dewpoint rapidly decreases with height
Radiation fog tends to form first in lower lying areas because: - Temperatures are warmer and moisture concentration is higher - Temperatures are cooler and moisture concentration is higher - Temperatures are warmer and moisture concentration is lower - Temperatures are cooler and moisture concentration is lower
Temperatures are cooler and moisture concentration is higher
The seasons of Spring, Summer, Winter, and Fall are a direct result of which phenomenon?
The 23.5 ° tilt of the Earth from vertical
In the vertical dimension, the upper level jet stream is located closest to which mandatory synoptic scale pressure level?
The 300 millibar level (9,500 meters)
Which of the following reasons explains why the stratosphere is absolutely stable. - Air temperatures are too cold - Air pressure is too low - The absorption of radiant energy by ozone - The wind speed is too strong
The absorption of radiant energy by ozone
What is meant by "the cold front and cold air mass is modifying"? - The front is gaining in forward speed - The air behind the front is not as cold as it once was - The cold front and cold air mass have dissipated - It means it is turning into a warm front
The air behind the front is not as cold as it once was
Define parallax:
The apparent displacement of a cloud due to the viewing angle of the satellite sensor
The LI is an assessment of (in)stability of an air parcel that begins the ascent from: - The boundary layer - 850 mb - 700 mb - 500 mb
The boundary layer
Shear vorticity is calculated as: - The change in wind speed over a change in distance - The change in wind direction over a change in distance - The change in temperature over a change in distance - The change in vertical motion over a change in distance
The change in wind speed over a change in distance
When comparing the moisture content in the air between two locations it is best to use?
The dewpoint
If heat is added to ice but the ice remain at a constant temperature, then: - The thermometer will detect a temperature change - Energy is not being added to the ice - Energy is being subtracted from the ice - The energy added to the ice is being absorbed due to a latent heat process
The energy added to the ice is being absorbed due to a latent heat process
Which of the following is true and explains why frost can form before the temperature cools to the dew point and explains why the temperature and dewpoint lines tend to diverge with height on a Skew-T even when the air is saturated with respect to ice: - The frost point is a lower temperature than the dew point - The frost point is a higher temperature than the dew point
The frost point is a higher temperature than the dew point
Which of the following weather analysis tools can be used to determine at a quick glance whether thunderstorms are most likely to be supercells, multicells, or air mass thunderstorms? - The value of CAPE - The 500 and 300 millibar analysis charts - The hodograph - Meso-ETA forecast panels
The hodograph
The dryslot on water vapor imagery, which usually wraps into a mid-latitude cyclone from the southwest, is created by which feature?
The jet stream
Virga is most likely to occur and a large amount of precipitation evaporated when: - The lower troposphere is warm and dry - The lower troposphere is cold and dry - The lower troposphere is warm and moist - The lower troposphere is cold and moist
The lower troposphere is warm and dry
Which of the following is true concerning convective instability: - The PBL is very dry - Warm less dense air flows over colder less dense air - The troposphere is made more stable when dynamic lifting occurs - The lower troposphere is warm and moist and the middle troposphere is dry
The lower troposphere is warm and moist and the middle troposphere is dry
(Statement 1) Classic supercells tend to produce stronger convective wind gusts and larger hail than HP supercells. T/F
True
What causes winter mid-latitude cyclones to intensify rapidly into very deep cold cored lows as they move from the central or southern US into the northeastern US and coastal northeast? They are often termed Nor'easters.
The release of enormous amounts of latent heat from Atlantic moisture and an enormous east to west temperature gradient
What is a weather pattern? - Weather that is typical - The climatology of a region - The same weather repeating for several days - A rapid change in the weather
The same weather repeating for several days
Which statement is true about rainbows?: - The secondary rainbow encompasses an 12° arc above the primary rainbow - A rainbow will not be seen by a surface observer if the sun is greater than 24° above the horizon - The secondary rainbow is always dimmer than the primary rainbow - Rainbows are most commonly seen in the early morning hours
The secondary rainbow is always dimmer than the primary rainbow
A storm can be shredded apart if: - It has too much moisture - The CAPE is too large - The low level convergence is too strong - The shear is too strong
The shear is too strong
Why does snow tend to have a smaller overall reflectivity as compared to rain?
The snow has a lower moisture content and ice generally has a lower reflectivity
You should "prepare for a blow" when: - The surface pressure is rapidly falling - The surface pressure is high
The surface pressure is rapidly falling
What is Theta-e? - The amount of positive buoyancy with respect to a surface based lifted parcel of air - The temperature in Kelvins of air that has had latent heat released and brought to the 1000 mb pressure surface - It is the amount of streamwise vorticity available for ingestion into a thunderstorm - It is how heat and humidity are combining to make it feel outside
The temperature in Kelvins of air that has had latent heat released and brought to the 1000 mb pressure surface
When forecasting snow amounts associated with winter mid-latitude cyclones, the most complete list of the primary synoptic scale ingredients and forecasting tools for heavy snow are:
The track of the low, intensity of low, PBL temperatures including 850 millibar temperature, isentropic lifting, precipitable water, 1000 to 500 millibar thickness, 500 millibar vorticity, and the speed of low
Taking of model consensus on the temperature forecast in many situations is a good idea. All of the following are good situations to take model consensus except: - There is a stagnant airmass over the forecast area - All the models have a common consensus - There are no clouds - The weather pattern is changing - The weather is typical to what should occur that time of the year
The weather pattern is changing
Why do surface afternoon summer temperatures tend to be warmer in southern Arizona than Mississippi when both states are at about the same latitude?
There is more evapotranspiration in Mississippi; evapotranspiration is a cooling process that absorbs latent heat
Why is the ITCZ mean position North of the Equator? - There is more ocean area in the Northern Hemisphere - The Coriolis force is stronger in the Northern Hemisphere - There tends to be lower pressure due to more landmass near the Northern Hemisphere equatorial region - The magnetic pole is in the Northern Hemisphere
There tends to be lower pressure due to more landmass near the Northern Hemisphere equatorial region
Thickness values can be used to infer the strength of:
Thermal advection
Which of the following is a direct sensor? - Radar - Satellite - Wind profiler - Thermometer
Thermometer
(Statement 1) If the PRF of a radar decreases, then the maximum unambiguous range will increase. (Statement 2) If the PRF of a radar decreases, the maximum unambiguous velocity will decrease. T/F
True
All the following are true about tornadoes EXCEPT: - A thunderstorm is required in order for a tornado to occur - They can either be in contact with the ground or only exist aloft as a funnel - Low level wind inflow, instability and wind shear are needed in order for a tornado to develop - A tornado will have a violently rotating column of air associated with it
They can either be in contact with the ground or only exist aloft as a funnel
Which of the following is false concerning a shortwave? - They have cyclonic curvature - They are smaller than longwaves - They often have rising air associated with them - They occur at the surface
They occur at the surface
The rate of evaporation depends least on: - Temperature of water and air - Relative humidity of air - Tidal influences - Wind speed - Amount of direct sunlight
Tidal influences
In which direction from a winter mid-latitude cyclone is heavy snow most likely to occur? The heaviest snow falls here due to the best combination of cold air and uplift. In this part of the cyclone, warm and moist air isentropically wraps up and over (wrap around precipitation) cold PBL air.
To the north
Where is the warm sector located in reference to a developed mid-latitude cyclone over the United States?
To the southeast
Which of the following on average produces the least weather related deaths per year? - Lightning - Tornadoes - Floods - Heat waves
Tornadoes
An "A" climate is characterized as having:
Tropical forest climates and hot all seasons
Which of the following is NOT a high latitude climate? - Polar - Tundra - Tropical wet and dry - Taiga
Tropical wet and dry
A region of divergence in the upper troposphere initiates upward vertical motion. Rising air cools and this helps create a ___________ aloft.
Trough
(Statement 1) Beam spreading and attenuation both combine to produce a much poorer sampling of storms far from the radar. (Statement 2) Storms and precipitation close to the radar degrade the radar energy before it reaches storms further from the radar. T/F
True
(Statement 1) In the standard atmosphere (average temperature at each height in troposphere) the temperature always decreases with height in the troposphere. T/F
True
(Statement 1) The Tropopause is at a higher elevation and lower pressure level in the warm season as compared to the cool season. (Statement 2) The tropopause is much more of a transition zone than a particular pressure level plane. T/F
True
(Statement 1) The difference between the high and low tends to be much greater on dry clear 24-hour days than on warm cloudy 24-hour days. (Statement 2) When the surface temperature drops to the surface dewpoint the cooling rate is decreased thereafter at night due to the latent heat of condensation release. T/F
True
(Statement 1) The jet stream is broken up into segments of higher velocity winds called jet streaks. Further, upper level closed lows can reverse the wind flow of the jet stream in some places. T/F
True
A surface cold front is a lifted mechanism. T/F
True
A very high sfc to 500 mb RH value (80% or greater) indicates that significant lifting will likely produce precipitation. T/F
True
Air moves from high pressure toward low pressure. T/F
True
Drier soils tend to promote cooler low temperatures than wet soils. T/F
True
Elevated convection is convection that has the lifting first begin above the boundary layer. It is convection not the result of surface based convection. T/F
True
If an afternoon rain falls preceding a clear night then the risk of fog increases. T/F
True
If the dewpoint depression is large during the afternoon, there will generally be a large temperature range between the high and low temperature especially on clear days and nights. T/F
True
If the upper level winds are weak, storm systems and thunderstorms will tend to move slower than when the upper level winds were strong. T/F
True
If there is more cloud cover during the daylight hours than expected then the high temperature will tend to be lower than expected. T/F
True
If there is no wind or no thermal gradient then warm air advection can not occur. T/F
True
Increasing the gain will increase the power returned to the radar. T/F
True
MOS is an integral part of putting together a specific temperature and precipitation forecast. T/F
True
Snow and ice can melt even when the air temperature remains below freezing during the day. T/F
True
Soil and ground temperatures take much longer to adjust to air temperatures than elevated structures. T/F
True
The frequency and wavelength of light detected by an observer depends on that observer's frame of reference. T/F
True
The resolution of radar data decreases with distance from the radar site. T/F
True
The rotational velocity of a mesocyclone is outbound plus inbound velocity divided by 2. T/F
True
The wind chill value is how cold a person feels when wind and temperature are combined. T/F
True
The winds within and around a tornado can vary by over 100 miles per hour over distances less than the size of a football field. T/F
True
There are some cases in which temperatures will actually warm after a cold front passage. T/F
True
Typical temperatures are the most common temperatures a location experiences. T/F
True
Water drops falling through warm and dry air will evaporate more quickly than water drops falling through cold and moist air. T/F
True
Water vapor moves from regions of high vapor pressure toward regions with low vapor pressure T/F
True
Windows will protect you more from harmful UV radiation as compared to the window not being there. T/F
True
A region of highest values of rising air due to forced lifting on the model progs is termed a: - Vort max - Jet streak - UVV max - Theta-E ridge
UVV max
The Storm Prediction Center's Convective Outlook is used to help the forecaster: - Issue severe thunderstorm warnings - Understand the reasons for the convective potential and where the convective potential and severe weather potential will most likely occur - Plan for the convective potential from now until 10 days into the future
Understand the reasons for the convective potential and where the convective potential and severe weather potential will most likely occur
The lifting of air that occurs with an upper level low commonly occurs through: - Converging of air masses - Increasing values of moisture - Cold air advection - Upper level divergence
Upper level divergence
Checking the weather conditions that will be advecting toward the forecast area is important since they will have an important impact on the future weather. A forecaster checks the weather conditions advecting toward the region by examining the: - Downstream conditions - Upstream conditions
Upstream conditions
Of the following choices, which is displayed on 700 millibar forecast charts such as ETA and the NGM?
Upward vertical velocity
The ______________ is the integration of reflectivity within a column of air. - VAD - RHI - VIL - CAPE
VIL
When dewpoint is plugged into the Clausius-Clapeyron equation the value determined is the: - Mixing ratio - Saturation mixing ratio - Vapor pressure - Saturation vapor pressure
Vapor pressure
Why is hail rare in a hurricane? - Intense instability - Very high freezing level - Dry air aloft - Lack of condensation nuclei - Weak winds aloft
Very high freezing level
All help contribute to a tornado alley in the plains region of the U.S. except: - High instability - Strong wind shear - Very moist air in middle and upper troposphere and weak winds aloft - Rich supply of low level moisture from the Gulf of Mexico - Fronts, mid-latitude cyclones and troughs are common
Very moist air in middle and upper troposphere and weak winds aloft
Cloud texture such as shadows and lumpiness are best seen on ____________ imagery.
Visible
What is specific volume? - Mass times acceleration - Force per unit area - Mass divided by volume - Density times gravity times height - Volume divided by mass
Volume divided by mass
All are displayed on the 1000-mb UNISYS model prog except: - Convergence - Wind vectors - Vorticity - Dewpoint
Vorticity
What is the feature at "F"? - Rear Flank Downdraft - Wall cloud - Rain / Hail core - Forward Flank Downdraft
Wall cloud
When 1000 to 500 mb thicknesses are increasing over the forecast area it is likely that __________ is occurring.
Warm Air Advection
A baseball when hit with the same force will tend to travel furthest in: - Cold and dry weather - Cold and moist weather - Warm and dry weather - Warm and moist weather
Warm and moist weather
Which type of pressure system is found in the southwest US in the summertime? Associated with this pressure system are hot afternoon temperatures, rising air in the PBL but very little precipitation and sinking air aloft.
Warm core low
Which of the following fronts GENERALLY has the smallest slope and is associated with light to moderate and widespread precipitation? This front is often found to the right of a mid-latitude cyclone in North America. - Cold front - Dryline - Warm front - Hurricane
Warm front
In order for a hurricane to develop, which ingredient of the choices below is needed: - Strong vertical wind shear - Very strong trade wind inversion - Warm sea surface temperatures - Broad region of surface high pressure
Warm sea surface temperatures
In which case is knowing the Lifted Index most relevant? - Warm sector severe thunderstorm situation - Winter storm situation - Tropical storm situation - Isentropic lifting situation
Warm sector severe thunderstorm situation
The definition of a variable gas is a gas that varies significantly from time to time and place to place. The most significant variable gas by volume in the planetary boundary layer in the atmosphere is:
Water vapor
The SRDS (Storm Relative Directional Shear) value is 15. This would indicate ___________ shear.
Weak
Wind speeds at the center of a closed trough tend to be __________.
Weak
Air mass thunderstorms tend to have an environment with: - Weak speed wind shear and weak directional wind shear - Strong speed wind shear and weak directional wind shear - Strong speed wind shear and strong directional wind shear - Weak speed wind shear and strong directional wind shear
Weak speed wind shear and weak directional wind shear
A pulse storm forms in an environment with: - Strong wind shear and strong instability - Strong wind shear and weak instability - Weak wind shear and strong instability - Weak wind shear and weak instability
Weak wind shear and strong instability
Wrap-around snow will typically occur on the _________ side of a low pressure system. - West - East
West
Many of the world's desert regions are located:
West coast regions along the Tropics of Capricorn and Cancer
The region of the U.S. dominated by highland climates is the: - Southeast region - Great Lakes region - Western region - Great Plains region
Western region
This is the temperature after complete evaporational cooling occurs: - Dewpoint - Wet bulb - Mixing ratio - Parcel temperature
Wet bulb
With the drops having equal mass, which of the following will have a higher reflectivity on radar?: - Wet snow - Dry snow - Rain - Sleet
Wet snow
The dewpoint can be determined when the values of temperature and ____________ are known. - Wet-bulb - Pressure - Air density - Wind speed
Wet-bulb
When is the MOS temperature forecast most likely to bust? - On a sunny day with light wind - Near the center of synoptic scale high pressure - In a barotropic environment - When a front or mid-latitude cyclone enters the forecast region
When a front or mid-latitude cyclone enters the forecast region
PVA occurs: - Immediately under the vort max - Where warm air advection occurs - Where higher values of vorticity are advected into the region - Most significantly in the boundary layer
Where higher values of vorticity are advected into the region
This term means, "spread or scattered over a considerable extent". - Widespread - Widely scattered
Widespread
The type of thermal advection that takes place depends primarily upon: - Solar radiation - Wind speed - Wind direction - Latent heat processes
Wind direction
What is a "variable wind"? - Wind direction often changes - A severe wind gust from a storm - A wind that is calm - A wind that is gusty
Wind direction often changes
What are straight-line winds? - Winds generated by a tornado - Wind gusts generated by a thunderstorm - Average wind speed on a typical day - Wind speed observed aloft where the influence of friction is not significant
Wind gusts generated by a thunderstorm
Severe thunderstorms in general tend to form in an environment initially with dynamic lifting, instability and: - Wind shear - Capping - Isentropic descent - Saturation within entire troposphere
Wind shear
The Helicity value is used to assess: - Wind shear - Instability - Moisture - Lifting mechanisms
Wind shear
The BRN (Bulk Richardson Number) assesses the balance between: - Moisture and lifting mechanisms - Wind shear and instability - Instability and Moisture - Lifting mechanisms and wind shear
Wind shear and instability
The EHI (Energy Helicity Index) combines two indexes to assess: - Moisture and lifting mechanisms - Wind shear and instability - Instability and Moisture - Lifting mechanisms and wind shear
Wind shear and instability
The sun is closest to the Earth in ______________, this is known as ______________ and has a ____________ effect on seasons. Assume you are in the Northern Hemisphere.
Winter; Perihelion; small
Which U.S. city is the driest? - Yuma, Arizona - Bismarck, North Dakota - Denver, Colorado - Salt Lake City, Utah
Yuma, Arizona
A morning capping inversion: - Can prevent afternoon storms from occurring - Can help build convective potential energy in the PBL during the day which can be released once the cap breaks
both
(Statement 1) The frost point is higher in temperature than the dewpoint. (Statement 2) The vapor pressure is less over ice than over water at the same temperature. T/F
both are true
(Statement 1) The gravitational field strength around an object depends upon the size of the object. (Statement 2) The gravitational attraction between two bodies decreases as the two bodies are displaced further away from each other. T/F
both true
The air behind the forward flank downdraft associated with strong thunderstorms consists of _________________ air while the rear flank downdraft consists of relatively __________________ air.
cool and moist; warm and dry
Which of the following is true of maritime polar air? - It has a high dewpoint - It has very warm temperatures - It has a high relative humidity - It forms over equatorial oceans
t has a high relative humidity
