Exam 14: Thunderstorms

Explain what a supercell thunderstorm is, and how this type of thunderstorm can lead to the formation of tornadoes.

Explain why ordinary cell thunderstorms tend to dissipate much sooner than multicell storms.

Where the cold downdraft reaches the surface, the air spreads out horizontally in all directions. The surface boundary that separates the advancing cooler air from the surrounding warmer air is called a ____________________.

Typically, a lightning flash will have ____ leaders, each followed by a return stroke.

Sound travels ____________________ in warm air than in cold air.

When a thunderstorm is located on the high plains east of the Rocky Mountains, a much larger portion of the storm will typically be located above the freezing level, so hail has a better chance of occurring.

____ lightning looks like a luminous sphere, often about the size of a football, that appears to float in the air or slowly dart about for several seconds

Cloud-to-ground lightning begins within the cloud when the localized electric potential gradient exceeds ____ volts per meter along a path perhaps 50 m long.

Which of the following is NOT a trigger needed to start air moving upward and thus causing thunderstorms?

Thunderstorms are ____________________ storms that form with rising air.

____________________ are placed on buildings to protect them from lightning damage.

Squall-line thunderstorms often form ahead of advancing cold fronts but seldom behind them.

A thunderstorm is a storm containing ____________________ and ____________________.

How does negative cloud-to-ground lightning differ from positive cloud-to-ground lightning?

Even though the bright return stroke of lightning travels from the ground up to the cloud, it happens so quickly that our eyes cannot resolve the motion, and we see what appears to be a continuous bright flash of light.

When caught in a thunderstorm in an open field, the best thing to do is to ____.

Thunderstorms typically form in the summertime during the warmest part of the day when the surface air is most unstable. In what part of the United States are thunderstorms most common in the winter and spring due to an inversion that inhibits the development of cumulus clouds?

Although we often see thunderstorms forming where the surface air is quite warm and humid, they may also form when the surface air temperature is 10 degrees Celsius (50 degrees Fahrenheit)or even lower.

The highest frequency of thunderstorms in the United States occurs in ____.

In the United States, winter thunderstorms often occur ____ when cold air aloft moves over the region.