Why do hurricanes form?
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Image sources: NASA and Weatherunderground.com used with permission for educational purposes.
Warm moist air condenses over the African rainforests during the summer.
Hot Saharan winds provide a kick to storms sending them out to Atlantic Ocean.
Clouds move out over the warm North Atlantic Ocean where they collect more moisture.
Trade winds drive the storms toward North America.
The Coriolis effect explains the counterclockwise spin around low pressure at the base of the storm.
Shearing winds are weak during the summer months, therefore cloud tops are able to hold together.
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Thunderstorms merge to form a tropical wave. Trade winds blow the storms west. The rotation of the earth helps give the counterclockwise spin to the growing storm (Coriolis effect). If the storms remain over 80 degree F water and in low wind shear, a tropical depression may form. Tropical depression are given a number. The next stage would be a stronger, more organized tropical storm. At this stage, the storm is given a name. When sustained wind speeds reach 74 mph, the storm becomes a hurricane. A tropical wave developed on June 17, 2006. Although one model projected the development of a tropical storm moving toward Bermuda, most predicted that strong shearing winds Strong shearing winds would keep the wave from becoming a significant storm system. Note the African dust in the satellite image. |
Image source: Weatherunderground.com used with permission for educational purposes.
Current Conditions over Africa
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