Category 1 (Minimal hurricane): Wind speed of 74-95 mph (64-82 knots). Damage primarily to shrubbery, trees, poorly constructed signs, and unanchored mobile homes. No significant damage to other structures. Storm surge 4-5 ft (1.0-1.7 m) above normal tide. Low-lying coastal roads inundated, minor pier damage, some small craft in exposed anchorages torn from moorings. Ex. Hurricane Jerry, 1989.
Category 2 (Moderate hurricane): Wind speed of 96-110 mph (83-95 knots). considerable damage to shrubbery and tree foliage; some trees blown down. Extensive damage to poorly constructed signs. Major damage to exposed mobile homes. Some damage to roofing materials of buildings; some wind and door damage. No major damage to buildings. Storm surge 6-8 ft (1.8-2.6 m) above normal tide. Coastal roads and low-lying escape routes made impassable by rising water 2-4 hr. before the arrival of the hurricane center. Considerable damage to piers; marinas flooded; small craft in unprotected anchorages torn from moorings. Evacuation of some shoreline residences and low-lying island areas required. Ex. Hurricane Bob, 1991.
Category 3 (Extensive hurricane): Wind speed of 111-130 mph (96-113 knots). Foliage torn from trees; large trees blown down. Practically all poorly constructed signs blown down. Some damage to small buildings. Mobile homes destroyed. Storm surge 9-12 (2.7-3.8 m) ft. above tide. Serious flooding at the coast and many small structures near coast destroyed; large structures near coast damaged by battering waves and floating debris. Low-lying escape routes made impassable by rising water 3-5 hr. before the hurricane center arrives. Flat terrain <5 ft above sea-level flooded inland >8 miles. Evacuation of low-lying residences within several blocks of shoreline possibly required. Ex. Hurricane Gloria, 1985.
Category 4 (Extreme hurricane): Wind speed of 131-155 mph (114-135 knots). Trees, shrubs, and all signs are blown down. Roofs, windows, and doors extensively damaged; complete failure of roofs on small structures. Mobile homes are completely destroyed. Storm surge is 13-18 ft. (3.9-5.6 m) above tide. Flat areas <10 ft. above sea level are flooded inland up to 6 miles inland. Major damage to the lower floors of structures near shore from flooding, forceful waves, and floating debris. Low-lying roads and escape routes made impassable by rising water 3-5 hours before the center of the hurricane arrives. Beaches erode significantly. Massive evacuation of all occupied residences within 500 yards of the shoreline and all single-story residences on low ground within 2 miles of the shore possibly required. Ex. Hurricane Andrew, 1992.
Category 5 (Catastrophic hurricane): Wind speed greater than 155 mph (135 knots). Large trees, shrubs, and all signs are blown down. Roofs heavily damaged with many roofs on small structures, residences, and industrial buildings completely failing. Windows and doors extensively damaged with breakage of glass sections. Some complete building failures with small buildings overturned or blown completely away, and remaining mobile homes completely destroyed. Storm surge is greater than 18 ft. (5.6 m) above tide. Major damage to lower floors of all structures less than 15 ft. above sea-level and within 500 yd. of the shore. Low-lying roads and escape routes made impassable by rising water 3-5 hours before the center of the hurricane arrives. Massive evacuation of all residences on low-ground and within 5-10 miles of the shore maybe required. Ex. Hurricane Camille, 1969.