Thunderstorms
Web Weather
Thunderstorms WebQuest
Thunderstorms
Formation, Types, Lightning and Thunder, Safety
Lightning and Thunder
Thunderstorms (FEMA for kids)
Thunderstorms (Fact Monster)
Thunderstorms and Lightning (Oahu)
Lightning Injury Research Program
Thunderstorms Words & Music
NASAexplores Express Lessons and Online Resources
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THUNDERSTORM (Infoplease Fact Monster Encyclopedia)
Thunderstorm, violent, local atmospheric disturbance accompanied by lightning, thunder,
and heavy rain, often by strong gusts of wind, and sometimes by hail. The typical
thunderstorm caused by convection occurs when the sun's warmth has heated a large body
of moist air near the ground. This air rises and is cooled by expansion. The cooling
condenses the water vapor present in the air, forming a cumulus cloud. If the process
continues, the summit often attains a height of 4 mi (6.5 km) above the base, and the
top spreads out in the shape of an anvil. The turbulent air currents within the cloud cause
a continual breaking up and reuniting of the raindrops, which may form hail, and builds up
strong electrical charges that result in lightning. As the storm approaches an area, the
gentle flow of warm air feeding the cloud gives way to a strong, chilly gust of wind from the
opposite direction, blowing from the base of the cloud. Intense rain begins, then gradually
diminishes as the storm passes. Night thunderstorms are caused by the cooling of the
upper layers of air by radiation; others are caused by approaching cold air masses that
advance as a wedge near the ground, forcing the warmer air in its path to rise. Even a
forest fire or a volcanic eruption may create a thunderstorm. Thunderstorms occur most
frequently in the equatorial zone (some localities have as many as 200 a year) and
seldom in the polar regions. In the United States they are most frequent along the E Gulf
Coast (averaging more than 70 a year) and least frequent on the Pacific coast (less than 4
a year).
Types of Thunderstorms (NexLab)
Thunderstorms: Thunder and Lightning
What Makes a Severe Thunderstorm?
Severe Storms Online Meterology Guide
Severe Thunderstorm (Red Cross)
Getting Started in Tornado and Thunderstorm Spotting
Types of Thunderstorms
single cell, multicell clusters, multicell lines and supercells
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A thunderstorm, or an electrical storm, is a form of weather characterized by the presence of lightning and its attendant thunder. It is usually accompanied by copious rainfall, hail, or, on occasion, snowfall in the winter months (which is sometimes known as thundersnow).
