Hurricanes are devastating weather systems characterized by low-pressure at the center, very strong winds, heavy rains and spiral thunderstorms.
The factors most commonly associated with formation of hurricane include, certain water temperature, rapid cooling, high humidity, low wind shear, distance from equator and pre-existing system of disturbed weather. The warm air over the ocean surface (typically in tropical regions) causes evaporation of water vapors which rise and condense to form clouds. This continued evaporation and condensation builds a column of clouds. This also causes hot rising air to cool down at the top of cloud cover. This loss of heat results in outward motion of air and causes rapidly rotating winds (towards a low pressure center). Over time, the storm builds and becomes a hurricane and is characterized by rapidly rotating winds, around a low pressure zone (called eye of storm) and heavy rains.
Forecasting of hurricanes make use of the factors mentioned above. Generally, the forecasting effort includes measurement of wind speeds at a certain altitude (~ 10,000 feet above sea level), position and strength of low pressure areas, satellite images and weather data coupled with computer models to determine the strength and extent of future hurricanes.
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