Category four hurricane: A hurricane with winds 131-155 mph (114-135 kt or 210-249 km/hr). Storm surge generally 13-18 ft above normal. More extensive curtainwall failures with some complete roof structure failures on small residences. Shrubs, trees, and all signs are blown down. Complete destruction of mobile homes. Extensive damage to doors and windows. Low-lying escape routes may be cut by rising water 3-5 hours before arrival of the center of the hurricane. Major damage to lower floors of structures near the shore. Terrain lower than 10 ft above sea level may be flooded requiring massive evacuation of residential areas as far inland as 6 miles (10 km).
Hurricanes are rated on a 1-5 scale based on the hurricane's intensity. The scale is used to give an estimate of the potential property damage and flooding expected along the coast from a hurricane landfall. Wind speed is the determining factor in the scale, as storm surge values are highly dependent on the slope of the continental shelf in the landfall region.
See: Saffir-Simpson hurricane scale.
The Saffir-Simpson Hurricane Wind Scale was updated in early 2010. Below are links to the updated documents which were accepted by the National Weather Service.
Category four hurricane: A hurricane with winds 131-155 mph (114-135 kt or 210-249 km/hr). Storm surge generally 13-18 ft above normal. More extensive curtainwall failures ...
Hurricane Dora surged to a major Category Four storm off Mexico's Pacific coast, lashing it with driving rain and rough waves, the National Weather Service said ...
MEXICO CITY—Hurricane Dora surged to a major Category Four storm off Mexico’s Pacific coast late Wednesday, lashing it with driving rain and rough waves, the ...
Category Four Hurricane (Sustained winds 131-155 mph, 114-135 kt, or 210-249 km/hr). Catastrophic damage will occur. There is a very high risk of injury or death ...