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Glossary of storm types

Your familiarity with storm types is likely based on where you live. Tornado Alley? The Sun Belt? The Frozen Tundra? But do you know the difference between a cyclone and a tornado? A hurricane and a typhoon? Now you can:

Blizzard -- Snow blown by winds with an average speed of at least 32 mph (52 km/h).

Cyclone -- A large area of low atmospheric pressure, characterized by inward-spiraling winds. Also the name used for a hurricane in the Indian Ocean and Western Pacific Ocean and typhoon in the Northwest Pacific Ocean.

Hurricane -- A tropical revolving storm with sustained wind speeds of more than 73 mph (118 km/h). Known as a cyclone in the Indian Ocean and Western Pacific Ocean or a typhoon in the Northwest Pacific Ocean.

Ice Storm -- Occurs as rain freezes on contact with the ground. Also known as freezing rain. Ice storms form when a layer of relatively warm air above the earth's surface causes falling snow to melt to rain but a shallow layer of cold air remains at the ground that keeps temperatures right at the ground below freezing.

Sand Storm -- A strong, dry wind blowing over the desert that raises and carries clouds of sand or dust often so dense it obscures the sun and reduces visibility almost to zero; also known as a dust storm. Known as a simoom (or simoon) in North Africa and Arabia and a haboob in the region of Sudan around Khartoum. Sandstorms also occur, although less frequently, in the southwest United States.

Thunderstorm -- A local storm produced by a cumulonimbus cloud and accompanied by lightning and thunder.

Tornado -- A violently rotating column of air extending between, and in contact with, a cloud and the surface of the earth. Generally spawned by thunderstorms, though they have been known to occur without the presence of lightning. The United States has the highest incidence of tornadoes in the world.

Typhoon -- A name of Chinese origin (meaning 'great wind') applied to the intense tropical cyclones which occur in the western-most part of the Pacific Ocean. Its characteristics are mirror hurricanes of the Atlantic Ocean and cyclones of the Bay of Bengal.

Sources: BBC, The Weather Channel,
Columbia Encyclopedia and National Weather Service