Hurricane Glossary

Eye is the center of a tropical storm or hurricane that is characterized a roughly circular area of light winds and rain-free skies.

Eyewall is an organized band of thunderstorms surrounding the eye that contains intense rainfall and very strong winds.

Hurricane is a tropical cyclone in which the maximum sustained surface wind is at least 74 mph.

Hurricane Watch is an announcement for specific coastal areas that hurricane conditions are possible within 36 hours.

Hurricane Warning is a warning that sustained winds of 74 mph or higher associated with a hurricane are expected in a specified coastal area in 24 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 continue, even though winds may be less than hurricane force.

Tropical Cyclone is a low pressure system that develops over tropical or subtropical waters, with organized deep convection and a closed surface wind circulation about a well-defined center.

Tropical Depression is a tropical cyclone in which winds are less than 38 mph.

Tropical Disturbance is the earliest stage of a tropical cyclone.

Tropical Storm is a tropical cyclone in which the maximum sustained surface wind speed ranges from 39 mph to 73 mph.

Tropical Storm Warning is warning that sustained winds within the range of 39 to 73 mph associated with a tropical storm are expected in a specified coastal area within 24 hours or less.

Tropical Storm Watch is an announcement for specific coastal areas that tropical storm conditions are possible within 36 hours.