Gale or Storm Warning:
When a hurricane moves within a few hundred miles of the coast, gale or storm warnings are issued, advising boaters to stay in port.

Hurricane:
Closed isobars, strong and very pronounced rotary circulation, sustained winds of 74 mph or more.

Tropical Cyclone:
A tropical cyclone is the general term for all cyclonic circulations originating over tropical waters, classified by form and intensity as follows:

Tropical Depression:
One or more closed isobars and some rotary circulation at surface, sustained winds less than 39 mph.

Tropical Disturbance:
Rotary circulation slight or absent at surface, but sometimes better developed aloft, no closed isobars (lines of equal atmospheric pressure) and no strong winds - a common phenomenon in the tropics.

Tropical Storm:
Closed isobars, distinct rotary circulation, sustained winds of 39-73 mph.

Warning:
The mentioned conditions are expected in a specific coastal area in 24 hours or less.

Watch:
An announcement that the mentioned conditions (tropical storm or hurricane) pose a possible threat to coastal areas, generally within 36 hours.

When a hurricane warning is issued, all precautions should be taken immediately. If the hurricane's path is unusual or erratic, the warnings may be issued only a few hours before the beginning of hurricane conditions strike.

Saffir-Simpson Scale

• Tropical Storm
  Winds 39-73 mph
• Category 1 Hurricane - winds 74-95 mph (64-82 kt)
  No real damage to buildings. Damage to unanchored mobile homes. Some damage to poorly constructed signs. Also, some coastal flooding and minor pier damage.
  - Examples: Irene 1999 and Allison 1995
• Category 2 Hurricane - winds 96-110 mph (83-95 kt)
  Some damage to building roofs, doors and windows. Considerable damage to mobile homes. Flooding damages piers and small craft in unprotected moorings may break their moorings. Some trees blown down.
  - Examples: Bonnie 1998, Georges (FL & LA) 1998 and Gloria 1985
• Category 3 Hurricane - winds 111-129 mph (96-113 kt) *Major
  Some structural damage to small residences and utility buildings. Large trees blown down. Mobile homes and poorly built signs destroyed. Flooding near the coast destroys smaller structures with larger structures damaged by floating debris. Terrain may be flooded well inland.
  - Examples: Keith 2000, Fran 1996, Opal 1995, Alicia 1983 and Betsy 1965
• Category 4 Hurricane - winds 130-156 mph (114-135 kt) *Major
  More extensive curtainwall failures with some complete roof structure failure on small residences. Major erosion of beach areas. Terrain may be flooded well inland.
  - Examples: Hugo 1989 and Donna 1960
• Category 5 Hurricane - winds 157 mph and up (135+ kt) *Major
  Complete roof failure on many residences and industrial buildings. Some complete building failures with small utility buildings blown over or away. Flooding causes major damage to lower floors of all structures near the shoreline. Massive evacuation of residential areas may be required.
  - Examples: Andrew (FL) 1992, Camille 1969 and Labor Day 1935