| Storm Classification | Description |
|---|
| Category 1 | Winds 119–153 km/hour (74–95 miles/hour). Storm surge generally 1–1.5 m (4–5 feet) above normal. No real damage to building structures. Damage primarily to unanchored mobile homes, shrubbery, and trees. Some damage to poorly constructed signs. Some coastal road flooding and minor pier damage. |
| Category 2 | Winds 154–177 km/hour (96–110 miles/hour). Storm surge generally 2–2.5 m (6–8 feet) above normal. Some roofing material, door, and window damage to buildings. Considerable damage to shrubbery and trees, with some trees blown down. Considerable damage to mobile homes, poorly constructed signs, and piers. Coastal and low-lying escape routes flood 2–4 hours before arrival of the hurricane center. Small craft in unprotected anchorages break moorings. Hurricane Frances of 2004 made landfall over the southern end of Hutchinson Island, Florida, as a Category 2 hurricane. |
| Category 3 | Winds 178–209 km/hour (111–130 miles/hour). Storm surge generally 2.5–3.5 m (9–12 feet) above normal. Some structural damage to small residences and utility buildings with a minor amount of curtain-wall failure. Damage to shrubbery and trees with foliage blown off trees and large trees blown down. Mobile homes and poorly constructed signs are destroyed. Low-lying escape routes are cut off by rising water 3–5 hours before arrival of the hurricane center. Flooding near the coast destroys smaller structures, with larger structures damaged by battering from floating debris. Terrain continuously lower than 1.5 m (5 feet) above sea level may be flooded 3 m (10 feet) inland or more. Evacuation of low-lying residences within several blocks of the shoreline may be required. Hurricanes Jeanne and Ivan of 2004 were Category 3 hurricanes when they made landfall in Florida and Alabama, respectively. Hurricane Katrina of 2005 made landfall near Buras-Triumph, Louisiana, with winds of 204 km/hour (127 miles/hour). Katrina will prove to be the costliest hurricane on record, with estimates of more than $200 billion in losses. |
| Category 4 | Winds 210–250 km/hour (131–155 miles/hour). Storm surge generally 3.5–5 m (13–18 feet) above normal. More extensive curtain-wall 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 off by rising water 3–5 hours before arrival of the hurricane center. Major damage to lower floors of structures near the shore. Terrain lower than 3 m (10 feet) above sea level may be flooded, requiring massive evacuation of residential areas as far inland as 15 km (9 miles). |
| Category 5 | Winds greater than 250 km/hour (155 miles/hour). Storm surge generally greater than 5 m (18 feet) above normal. Complete roof failure on many residences and industrial buildings. Some complete building failures with small utility buildings blown over or away. All shrubs, trees, and signs blown down. Complete destruction of mobile homes. Severe and extensive window and door damage. Low-lying escape routes are cut off by rising water 3–5 hours before arrival of the hurricane center. Major damage to lower floors of all structures located less than 4.5 m (15 feet) above sea level and within 500 m (1650 feet) of the shoreline. Massive evacuation of residential areas on low ground within 15–20 km (9–12 miles) of the shoreline may be required. Only three Category 5 hurricanes have made landfall in the United States since records began. Hurricane Andrew of 1992 made landfall over southern Miami-Dade County, Florida, causing $26.5 billion in losses—the second costliest hurricane on record. |