Panama City condominium damaged by Hurricane Opal
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FEMA

Storm Strength

A cyclone is an area of low pressure with winds blowing counter-clockwise around it in the Northern Hemisphere and clockwise around it in the Southern Hemisphere. A tropical cyclone is a cyclone which forms in the tropics--imagine that.

Tropical cyclones are given different names to show how fast their winds are. Here is a list of the different names given to the storms:

Tropical Disturbance: Winds weak and unorganized
Tropical Depression: Winds less than 39 mph
Tropical Storm: Winds 39 to 74 mph
Hurricane: Winds greater than 74 mph

Also, meteorologists use the wind speed as one indicator as to how much damage a hurricane can do. Knowing what may be damaged lets officials know what areas they should evacuate.

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