MAIN Science Meteorology Tornadoes

Thunderstorms are the breeding ground for tornadoes, as high winds rapidly swirl to create a violent vortex that can cut a swath of destruction for miles around.

The larger the thunderstorm, the greater chance there is of a tornado funnel forming, especially where atmospheric conditions result in sudden and violent changes of wind direction and speed.

Tornado warning signs

From the ground, the most common warning signs that a tornado may be forming is when dark clouds (accompanied by lightning strikes) begin to take on an ominous green color, and when large hail begins to fall.

Along with the visual evidence, the terrifying sound of a tornado has often been likened to that of a roaring freight train.

USA - Tornado Central

While tornadoes in varying strengths can form in many parts of the world, the United States is home to the most violent and destructive tornadoes on the planet, causing almost 100 fatalties and more than 1,500 injuries each year. This is especially true of the Tornado Alley region ecompassing a large swath of southern and western U.S.

More about tornadoes around the Web:

Tornadoes ... Nature's Most Violent Storms - Excellent illustrated overview with information on what causes tornandoes and how they form, tornado facts & myths, clues as to when a tornado may strike, safety tips & advice, guides to related disaster plans for schools, families and institutions.

The Tornado Project - A digital library of facts & information including tornado myths & oddities, personal tornado stories, tornado chasing, safety tips & advice, lists of most powerful and destructive tornadoes, online store offering tornado books, videos.

National Geographic - Tornadoes - Stunning photos and videos, plus related news & feature stories, safety tips.

The Online Tornado FAQ - Extensive Q&A on tornado basics, forecasting, tornado spotting & chasing, related scientific research, historic tornadoes, safety guide.

Tornado Safety - Tornado Facts - Information, photos and related statistics from the Oklahoma Climatological Survey.

FEMA for Kids - Tornadoes - Kid-friendly facts, photos and information about tornado dangers including safety tips, first-person accounts, tornado drawings, related games & video.

Tornado in a Bottle - Fun & fascinating science class project with complete instructions and materials list for creating a vortex using two soda bottles.

also see -> Camping & Weather Safety Tips