Quiz Week 10

A sounding shows a temperature of -5 degrees Celsius at an altitude of 3 kilometers and a surface temperature of 25 degrees Celsius. Determine the average environmental lapse rate from the surface up to 3 kilometers.

10 degrees Celsius per km

Suppose a typical warm front with a slope of 1 to 200 is moving northward from the Gulf of Mexico. By the time it reaches St. Louis, how high would one need to rise above Minneapolis (460 miles away) to reach the overrunning warm air?

2.30 miles

Unlike midlatitude cyclones that form at the boundary between warm and cold fronts, tropical cyclones form over warm waters where the air is relatively homogeneous. The warm air and waters ensure ample water vapor that fuels the storms. What is the approximate range of ocean temperatures in the region of the North Atlantic Ocean and Gulf of Mexico in which tropical cyclones form?

24-29

A front travels the distance between Minneapolis and St. Louis (500 miles) in 17 hours. What is the average speed of the front?

30 mph

Suppose a typical cold front with a slope of 1 to 100 moving southward reaches St. Louis. If a sounding at a station north of St. Louis identifies warm air displaced by the front at a height of 0.4 km , about how far from St. Louis is this station located?

40 km

If you observe short, intense, scattered rainfall as a front passes, which of the following are you most likely to be experiencing?

A cold front

Which of the following best defines an air mass?

A large body of air with similar temperature and moisture characteristics

Cyclogenesis begins along a polar front where cold and warm air masses converge. As an upper-level disturbance moves over the front, a wave develops and the system forms a low-pressure center. Based on the hypothetical weather map, which of the following statements is correct?

A large midlatitude cyclone in the open stage has formed over the Upper Midwest (i.e. Minnesota, Wisconsin, and Michigan).

Which of the following best describes the phenomenon that typically develops at the surface beneath an area of divergence in the upper atmosphere?

A low pressure system

Which of the following best defines a front?

A narrow boundary separating different air masses

Within a Rossby wave, which of the following locations generally has the largest absolute vorticity?

At the trough axis

Which of the following terms best describes a situation in which isotherms and height contours are aligned in the same direction?

Barotropic

Which of the following is the coldest type of air mass?

Continental Arctic

What is the name for an air mass that forms over a large, high-latitude landmass with very low temperatures?

Continental Polar

Which of the following best describes the extremely hot, dry, and often cloud-free air masses that form during the summer over hot, low-latitude areas?

Continental Tropical air masses

The high temperature and low moisture content on this sounding (the figure below) indicate what kind of air mass?

Continental tropical

Which of the following forces works to create cyclonic and anticyclonic wind circulation patterns?

Coriolis effect pressure gradient surface friction

By the end of the forecast period, where should the maximum divergence at 500

Downstream of the trough axis, from Minnesota to Colorado

In which of the following areas is cyclogenesis most likely to occur?

In regions of strong temperature contrasts

How does the maximum absolute vorticity within the main Rossby Wave change over the forecast period?

It increases and becomes concentrated in the trough axis.

Cyclones and anticyclones are both rotational wind systems, but they differ significantly in many ways: Where are cyclones and anticyclones found in the Northern and Southern Hemispheres? In this activity, you will identify whether low- and high-pressure systems in the two hemispheres are associated with cyclonic or anticyclonic winds and how those winds will act. Drag the appropriate labels to their respective targets. Each label may be used only once.

Left to right: convergent counterclockwise, divergent counterclockwise, divergent clockwise, convergent clockwise

What is the name for an air mass that develops over warm tropical waters and is warm, moist, and unstable near the surface?

Maritime Tropical

Which of the following air mass types generally has the highest dew point?

Maritime Tropical

Which of the following is NOT part of the conveyor belt model?

Maritime conveyor belt

What are midlatitude cyclones?

Migrating low-pressure cells that move in the band of the westerlies

The warm air and oceans ensure there is abundant water vapor to fuel tropical cyclones. Nonetheless, winds also play a very important role in tropical cyclone development. What are the prevailing winds in the region of the North Atlantic Ocean and Gulf of Mexico in which tropical cyclones form?

Northeast trade winds

Which of the following best describes midlatitude cyclones that move along the U.S. East Coast and bring moist maritime air towards New England, often producing cold winds and heavy snowfall in winter?

Northeasters

In classical cyclogenesis, what is the last stage in the life of a midlatitude cyclone in North America?

Occlusion

What is occlusion in a midlatitude cyclone?

Occlusion is the process by which a cold front overtakes a warm front.

How are rain patterns different near warm and cold fronts?

Rain near a cold front occurs over a smaller spatial area and is more intense than near a warm front.

Where does rain occur in a cold front?

Rain occurs along and behind a cold front.

Where does rain occur in a warm front?

Rain occurs along and in front of a warm front.

Why does rain occur near a cold front?

Rising warm air cools, resulting in cloud formation and rain.

Why does rain occur near a warm front?

Rising warm air cools, resulting in cloud formation and rain.

At which of the following levels does the wind direction most closely approximate the path that a midlatitude cyclone tends to take?

The 500 mb level

Which of the following statements about movement in midlatitude cyclones are accurate?

The cold front advances faster than the center of the storm, and the warm front advances more slowly than the center. Surface winds move counterclockwise. The entire cyclone moves from west to east.

All tropical cyclones need warm air and water to be sustained. As a tropical cyclone approaches land or experiences cooler temperatures, they will weaken. Locate the hurricane on the surface weather map. Taking into account ocean currents, which answer best describes how the hurricane might change if it moves northeastward, following the Gulf Stream along the east coast of the United States?

The hurricane may strengthen because it will gain more energy from the warm waters of the Gulf Stream.

Which of the following best describes how polar fronts relate to the midlatitude cyclones shown in this video?

The polar front plays a role in the formation of many midlatitude cyclones.

The theory postulated in the early part of the twentieth century to describe the formation, development, and dissipation of midlatitude cyclones is known as which of the following?

The polar front theory

What determines whether a front is called a cold front or a warm front?

The type of front is determined by which air mass is moving.

Follow the path of the winter storm in the video. Which of the following does NOT explain why this winter storm produced so much precipitation?

The winter storm started in California.

Which of the following terms best describes the rotation of a fluid?

Vorticity

What happens when air masses of different temperatures meet?

Well-defined boundaries form between the air masses.

When do midlatitude cyclones stop producing storms?

When the cold front has completely taken over the warm front

Air masses are classified according to the latitude of their source regions: tropical, polar, or arctic. How else are air masses classified?

Whether they form in a continental (dry) or maritime (moist) source region

Which of the following best describes how much advance warning people typically have before powerful midlatitude cyclones like this one arrive?

a few days

If a front is moving at a rate of 30 mph, it is probably which of the following?

cold front

Which of the following locations has the highest concentration of water vapor?

equator

Why are there some areas displayed in the video with reflected radar signals that aren't moving in the generally west-to-east pattern with all the storm systems?

insects, birds, and ground clutter

Which of the following elements in the video explains how forecasting helped the people shown in the video to prepare for the midlatitude cyclone?

many grocery store shelves were nearly empty

The air temperature and moisture characteristics of the lower atmosphere on this sounding (the figure below) suggest the presence of which type of air mass?

maritime polar

The high air temperature and high dew point on this sounding (the figure below) indicate what type of air mass?

maritime tropical

What is a front?

the boundary between two air masses of different temperatures

Which of the following does NOT describe an effect of this particular midlatitude cyclone?

tornado

Which of the following best describes the bright, compact, rapidly swirling features in Earth's oceans?

tropical storms

Which of the following best describes what is going on when isobars (the yellow lines) are very close to each other?

very windy