6 Storms and Severe Weather Free Online FlashCards

How does a thunderstorm develop?

A thunderstorm develops when moist, unstable air rises and forms a tall cloud, often a cumulonimbus cloud.

What qualifies a thunderstorm as severe in the United States?

In the United States, a thunderstorm is severe if it produces a tornado, wind gusts of at least 58 miles per hour, or hail at least 1 inch in diameter.

How does hail form in a thunderstorm?

Strong updrafts carry water droplets into freezing parts of a cloud, where they grow into ice stones.

When should you take lightning shelter, and how long should you stay?

At the first sound of thunder, shelter in a substantial enclosed building or a hard-topped vehicle with closed windows. Stay sheltered for 30 minutes after the last thunder.

What is a tornado?

A tornado is a violently rotating column of air that extends from a thunderstorm to the ground.

How can wind shear contribute to tornado formation?

Wind shear is a change in wind speed or direction with height. It can help create rotation in organized severe thunderstorms.

How does the Enhanced Fujita scale rate tornadoes?

The Enhanced Fujita scale rates tornadoes from EF0 to EF5, using damage surveys to estimate their intensity.

What is the difference between a weather watch and a warning?

A watch means hazardous weather is possible, so be ready. A warning means the hazard is occurring or imminent, so take protective action.

Where should you shelter from a tornado inside a sturdy building?

In a sturdy building, go to a basement or a small interior room on the lowest floor, stay away from windows, and protect your head.

What sustained wind speeds mark a tropical storm and a hurricane?

In the Atlantic and eastern North Pacific, a tropical cyclone is a tropical storm at sustained winds of 39 miles per hour and a hurricane at 74 miles per hour.

What is storm surge, and why is it dangerous?

Storm surge is abnormal ocean water pushed onto the coast by a storm. It can cause destructive coastal flooding and travel inland.

What does a hurricane category not tell you?

The Saffir–Simpson Hurricane Wind Scale classifies hurricanes by wind speed, but a category does not describe every danger the storm may bring.