Back to Basic Definitions
Page | Back
to Main FAQ Page
Subject: A1) What is a hurricane, typhoon, or
tropical cyclone?
NOAA
Contributed by Chris Landsea
The terms "hurricane" and "typhoon" are regionally
specific names for a strong "tropical cyclone". A tropical
cyclone is the generic term for a non-frontal synoptic scale
low-pressure system over tropical or sub-tropical waters with
organized convection (i.e. thunderstorm activity) and definite
cyclonic surface wind circulation
(Holland 1993).
Tropical cyclones with maximum sustained
surface winds of less than 17 m/s (34 kt, 39 mph) are
called "tropical depressions" (This is not
to be confused with the condition mid-latitude people get during
a long, cold and grey winter wishing they could be closer to the
equator ;-)). Once the tropical cyclone reaches winds of at least
17 m/s (34 kt, 39 mph) they are typically called a
"tropical storm" and assigned a name. If winds reach 33 m/s
(64 kt, 74 mph)), then they are called:
- "hurricane" (the North Atlantic Ocean, the Northeast
Pacific Ocean east of the dateline, or the South Pacific Ocean
east of 160E)
- "typhoon" (the Northwest Pacific Ocean west of the dateline)
- "severe tropical cyclone" (the Southwest Pacific Ocean
west of 160E or Southeast Indian Ocean east of 90E)
- "severe cyclonic storm" (the North Indian Ocean)
- "tropical cyclone" (the Southwest Indian Ocean)
(Neumann 1993).
Back to Basic Definitions
Page | Back
to Main FAQ Page
|