Saffir - Simpson Hurricane Scale
Category 1: 74-95 mph winds
Effects: No real damage to building structures. Damage primarly to unanchored mobile homes, shrubbery, and trees. Also, some coastal road flooding and minor pier damage. Hurricane David, 1979
Category 2: 96-110 mph winds
Some roofing material, door, and window damage to buildings. Considerable damage to vegetation, mobile homes, and piers. Coastal and low-lying escape routes flood 2-4 hours before arrival of center. Small craft in unprotected anchorages break moorings. Example: Hurricane Bonnie, 1998
Category 3: 111-130 mph winds
Some structural damage to small residences and utility buildings with a minor amount of curtainwall failures. Mobile homes are destroyed. Flooding near the coast destroys smaller structures with larger structures damaged by floating debris. Terrain continuously lower than 5 feet ASL may be flooded inland 8 miles or more. Hurricane Fran, 1996
Category 4: 131-155 mph winds
More extensive curtainwall failures with some complete roof strucutre failure on small residences. Major erosion of beach. Major damage to lower floors of structures near the shore. Terrain continuously lower than 10 feet ASL may be flooded requiring massive evacuation of residential areas inland as far as 6 miles. Hurricane Hugo, 1989; Hurricane Floyd, 1999
Category 5: 155 mph and greater winds
Complete roof failure on many residences and industrial buildings. Some complete building failures with small utility buildings blown over or away. Major damage to lower floors of all structures located less than 15 feet ASL and within 500 yards of the shoreline. Massive evacuation of residential areas on low ground within 5 to 10 miles of the shoreline may be required. Hurricane Andrew, 1992; Hurricane Mitch, 1998
Hurricane Watch vs. Hurricane Warning
A hurricane watch is issued when there is a threat of hurricane conditions within 24-36 hours.
A hurricane warning is issued when hurricane conditions (winds of 74 miles per hour or greater, or dangerously high water and rough seas) are expected in 24 hours or less.