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A tropical cyclone is a low pressure system not associated with a cold front,
that develops over tropical and sometimes sub-tropical waters, and has an
A tropical depression is a tropical cyclone in which the maximum sustained
surface winds (a one minute average) are 38 miles per hour (33 knots) or
A tropical storm is a tropical cyclone in which the maximum sustained surface
winds range from 39 to 73 miles per hour (34 to 63 knots). The number of
Tropical Storms and Hurricanes increases substantially in August, peaks in
mid-September, and decreases towards a minimum by early November.
A hurricane is a tropical cyclone in which the maximum sustained surface
winds are 74 miles per hour or greater (64 knots or greater).
Tropical Storm Watch
A Tropical Storm Watch is issued when Tropical Storm conditions, including
winds from 39 to 73 miles per hour, pose a possible threat to a specified
coastal area within 48 hours.
Tropical Storm Warning
A Tropical Storm Warning is issued when Tropical Storm conditions, including
winds of from 39 to 73 miles per hour, are expected in a specified coastal
area within 36 hours or less.
A Hurricane Watch is issued for a specified coastal area for which a hurricane
a or an incipient hurricane condition is a possible threat within 48 hours.
A Hurricane Warning is issued when sustained wind of 74 miles per hour or
higher, caused by a hurricane, are expected in a specified coastal area in
36 hours or less.
A Hurricane Warning can remain in effect when dangerously high water or a
combination of dangerously high water and exceptionally high waves continues,
even though the winds may have subsided below hurricane intensity.