Hurricane: Know the Terms
Familiarize yourself with these terms to help identify a hurricane hazard:
Tropical Depression
An organized system of clouds and thunderstorms with a defined surface
circulation and maximum sustained winds of 38 MPH (33 knots) or less.
Sustained winds are defined as one-minute average wind measured at
about 33 ft (10 meters) above the surface.
Tropical Storm
An organized system of strong thunderstorms with a defined surface
circulation and maximum sustained winds of 39–73 MPH (34–63 knots).
Hurricane
An intense tropical weather system of strong thunderstorms with a
well-defined surface circulation and maximum sustained winds of 74 MPH
(64 knots) or higher.
Storm Surge
A dome of water pushed onshore by hurricane and tropical storm winds.
Storm surges can reach 25 feet high and be 50–1000 miles wide.
Storm Tide
A combination of storm surge and the normal tide (i.e., a 15-foot storm
surge combined with a 2-foot normal high tide over the mean sea level
created a 17-foot storm tide).
Hurricane/Tropical Storm Watch
Hurricane/tropical storm conditions are possible in the specified area,
usually within 36 hours. Tune in to NOAA Weather Radio, commercial
radio, or television for information.
Hurricane/Tropical Storm Warning
Hurricane/tropical storm conditions are expected in the specified area, usually within 24 hours.
Short Term Watches and Warnings
These warnings provide detailed information about specific hurricane threats, such as flash floods and tornadoes.
