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The Saffir-Simpson Hurricane ScaleA Tool Used to Estimate Storm Damage and Flooding
The Saffir-Simpson Hurricane Scale was developed by Herbert Saffir and Robert Simpson to estimate property damage and flooding caused by a hurricane with wind speed
The Saffir-Simpson (SS) Hurricane Scale is a tool used to rate hurricanes based on wind speeds measured before the storm arrives and estimate the damage it may cause. Herbert Saffir, a consulting engineer in Dade County, Florida, first modeled the scale as a way estimate the damage structures would experience at various wind speeds. Robert Simpson, a director of the National Hurricane Center, was an advocate for providing actual wind speed estimates of approaching storms to the public. It was a radical change in forecast policy in 1969 that went on to provide better and more convincing information to the public of approaching storms. The Saffir-Simpson Hurricane Scale divides hurricanes into five different classes according to wind speed, estimated flooding and property damage. It goes beyond the detail provided for hurricanes in the Beaufort Wind Force Scale. Category One Hurricane: Winds 119-153 km/hr (74-95 mph) Storm surge is generally 1.2 to 1.5 meters (4-5) ft above normal. No real damage occurs to buildings. Damage is limited primarily to unanchored mobile homes, shrubs, and trees. There is the possibility of coastal road flooding and minor damage to piers. Example storms: 2002's Hurricane Lili on the Louisiana coast and 2004's Hurricane Gaston on the South Carolina coast. Category Two Hurricane: Winds 154-177 km/hr (96-110 mph) Storm surge is generally 1.8 to 2.4 meters (6-8) feet above normal. The roofs, doors and windows of some buildings may be damaged. Damage to mobile homes, shrubs, trees, poorly built signs, and piers is considerable. Coastal and low lying escape routes will flood two to four hours before the eye of the hurricane comes ashore. Small boats will break free of their moorings in unprotected anchorages. Example storms: 2004's Hurricane Frances on Hutchinson Island, Florida and 2003's Hurricane Isabel on the Outer Banks of North Carolina. Category Three Hurricane: Winds 178-209 km/hr (111-130 mph) Storm surge is generally 2.7 to 3.7 meters (9-12 ft) above normal. Damage will occur to shrubs, foliage blown off trees, and larger trees are blown over. Mobile homes are destroyed. Coastal and low lying escape routes will flood three to five hours before the eye of the hurricane comes ashore. Coastal flooding destroys smaller buildings and floating debris damages larger structures. Continuous terrain under 1.5 meters above sea level may be flooded up to 13 kilometers (8 miles) inland. Evacuation of low-lying residences near the shore will be required. Example storms: 2004's Hurricane Jeanne on the coast of Florida and Hurricane Ivan on the coast of Alabama. Category Four Hurricane: Winds 210-249 km/hr (131-155 mph) Storm surge is generally 4.0 to 5.5 meters (13-18 ft) above normal. Some buildings will experience curtain wall failures and some smaller residences will have complete roof failures. Mobile homes are completely destroyed. Damage to doors, windows and roofs is extensive. Coastal and low lying escape routes will flood three to five hours before the eye of the hurricane comes ashore. Lower floors of buildings near shore suffer major damage. Terrain under 3.0 meters above sea level may flood and require major evacuation of residential areas up to 10 kilometers (6 miles) inland. Example storms: 2004's Hurricane Charley on Charlotte County, Florida and 2005's Hurricane Dennis on the Island of Cuba. Category Five Hurricane: Winds greater than 249 km/hr (155 mph) Storm is surge generally greater than 5.5 meters (18 ft) above normal. Many buildings have complete roof failures. Some buildings fail completely and smaller utility buildings are blown away. Shrubs, signs and trees are blown over. Mobile homes are completely destroyed. Windows and doors are extensively damaged. Coastal and low lying escape routes will flood three to five hours before the eye of the hurricane comes ashore. Lower floors of all structures less than 4.6 meters (15 ft) above sea level and within 0.5 kilometers (500 yards) suffer extensive damage. Major evacuation of residential areas in low-lying areas may be required up to 16 kilometers (10 miles) inland. Example storms: Only three Category Five hurricanes have come ashore in the United States since record keeping started. They were the Labor Day Hurricane of 1935, Hurricane Camille in 1969, and Hurricane Andrew in 1992. While Hurricane Katrina was initially a Category Five storm, it was a Category Three hurricane when it struck Louisiana in 2005. Official estimates place the property damage from Katrina at more than $81 billion.
The copyright of the article The Saffir-Simpson Hurricane Scale in Boating & Sailing is owned by Alan Sorum. Permission to republish The Saffir-Simpson Hurricane Scale in print or online must be granted by the author in writing.
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