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Storm warnings
By Times staff
© St. Petersburg Times
published May 26, 2002
By definition
By international agreement, tropical cyclone is the general term for all cyclonic, counterclockwise circulations originating over tropical waters, classified by form and intensity as follows:
Tropical disturbance - A rotary circulation with little to no development on the ocean surface but better development in the upper atmosphere and no strong winds, a common phenomenon in the tropics.
Tropical depression - A low-pressure area with some rotary circulation on the ocean surface and a sustained wind speed of less than 39 mph.
Tropical storm - A low-pressure area with a distinct rotary circulation and sustained wind speeds of 39 to 73 mph.
Hurricane - A low-pressure area with a strong and pronounced rotary circulation and a sustained wind speed of at least 74 mph.
Categorical strength
The Saffir-Simpson scale is used to rate the strength of hurricanes:
- Category 1 - Winds of 74 to 95 mph. Damage: minimal
- Category 2 - Winds 96 to 110 mph. Damage: moderate
- Category 3 - Winds 111 to 130 mph. Damage: major
- Category 4 - Winds 131 to 155 mph. Damage: severe
- Category 5 - Winds above 155 mph. Damage: catastrophic
Advisories
- Advisory - A way of disseminating hurricane and storm information to the public every six hours.
- Special Advisory - A warning given any time there is a significant change in weather conditions or change in warning.
- Intermediate Advisory - A way of updating regular advisory information every two to three hours if necessary.
- Gale Warning - Wind speeds of 39 to 54 mph expected.
- Storm Warning - Wind speeds of 55 to 74 mph expected.
- Hurricane Watch - A hurricane may threaten the area within 36 hours.
- Hurricane Warning - A hurricane is expected to strike the area within 24 hours or less.
- Evacuation Order - The most important instruction you will receive. Once issued, an evacuation order is mandatory under state law.
2002 storm names
Arthur, Bertha, Cristobal, Dolly, Edouard, Fay, Gustav, Hanna, Isidore, Josephine, Kyle, Lili, Marco, Nana, Omar, Paloma, Rene, Sally, Teddy, Vicky, Wilfred
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