14.4 Severe Weather Flashcards
Fujita scale
A scale measuring tornado intensity based on wind speed. The Fujita scale ranges from F0 to F5.
Funnel cloud
A spinning cylinder of air that descends from a severe thunderstorm but does not reach the ground.
Hurricane
A large, rotating, low-pressure system with sustained winds of at least 119 km/hr, and that forms over warm tropical oceans. Hurricanes are called typhoons in the western Pacific Ocean and cyclones in the Indian Ocean.
Saffir-Simpson scale
A scale that rates hurricanes based on their maximum sustained wind speeds. The Saffir-Simpson scale ranges from category 1 through 5.
Severe weather watch
An announcement alerting the public that weather conditions are favorable for the development of severe weather.
Severe thunderstorm
A thunderstorm that is capable of producing strong, gusty winds, large hail, heavy precipitation, and tornadoes.
Severe weather warning
An announcement warning the public that severe weather with a risk to life and property is imminent.
Squall line
A line of severe thunderstorms that may extend in a line hundreds of kilometers long.
Storm surge
An abnormal rise of sea level due to strong winds pushing a mound of seawater toward coastal areas, especially during hurricanes.
Supercell thunderstorm
A large, rotating, severe thunderstorm that may last for many hours.
Thunderstorm
A local storm with thunder and lightning produced by cumulonimbus clouds.
Tornado
An intense, rotating column of air that descends from a severe thunderstorm and reaches Earth’s surface.
Tropical depression
A slowly-rotating mass of thunderstorms and clouds with maximum wind speeds of 37-63 km/hr (23-39 mph) that forms over warm tropical oceans. Tropical depressions may develop into tropical storms.
Tropical storm
A large rotating mass of thunderstorms with maximum wind speeds of 63-118 km/hr (39-73 mph) that develops from a tropical depression. Tropical storms may develop into hurricanes.
Wind shear
A significant change of wind speed or direction with altitude.
