Hurricane: Formed when sustained winds reach 74 mph.
Hurricane Warning: Hurricane conditions are expected within the next 24 hours.
Hurricane Watch: Hurricane conditions are a possible threat within the next 36 hours.
Tropical Storm: Formed when sustained winds reach 39 mph.
Tropical Depression: Formed when a tropical wave develops cyclonic (counter-clockwise) circulation with sustained (one minute) winds up to 38 mph.
Tropical Disturbance/Tropical Wave: A grouping or cluster of clouds moving through the tropics.