Most of the information provided here was taken from The Red Cross, Hurricanes: A Preparedness Guide, and from information provided by the Storm Prediction Center.
A hurricane is a type of tropical cyclone-the general term for all circulating weather systems (counterclockwise in the Northern hemisphere) over tropical waters. Tropical cyclones are classified as follows:
Tropical Depression- An organized system of clouds and thunderstorms with a defined circulation and maximum sustained winds of 38 mph (33 knots) or less.
Tropical Storm- An organized system of strong thunderstorms with a defined circulation and maximum sustained winds of 39 to 73 mph (34-63 knots).
Hurricane- An intense tropical weather system with a well defined circulation and maximum sustained winds of 74 mph (64 knots) or higher. In the western Pacific, hurricanes are called "typhoons," and similar storms in the Indian Ocean are called "cyclones."
Hurricanes are products of the tropical ocean and atmosphere. Powered by heat from the sea, they are steered by the easterly trade winds and the temperate westerlies as well as by their own ferocious energy. Around their core, winds grow with great velocity, generating violent seas. Moving ashore, they sweep the ocean inward while spawning tornadoes and producing torrential rains and floods. Each year on average, ten tropical storms (of which six become hurricanes) develop over the Atlantic Ocean, Carribean Sea, or Gulf of Mexico. Many of these remain over the ocean. However, about five hurricanes strike the United States coastline every 3 years. Of these five, two will be major hurricanes (category 3 or greater on the Saffir-Simpson Hurricane Scale).
| Category | Sustained Winds (MPH) | Damage |
| 1 | 74-95 | Minimal |
| 2 | 96-110 | Moderate |
| 3 | 111-130 | Extensive |
| 4 | 131-155 | Extreme |
| 5 | >155 | Catastrophic |
The United States has a significant hurricane problem. There are now some 45 million permanent residents along the hurricane-prone coastline, and the population is still growing. The most rapid growth has been in the sunbelt from Texas through the Carolinas. Florida, where hurricanes are most frequent, leads the Nation in new residents. In addition to the permanent residents, the holiday, weekend, and vacation populations swell in some coastal areas 10- to 100-fold.
• All Atlantic and Gulf coastal areas are subject to hurricanes or tropical storms.
• Parts of the Southwest United States and Pacific Coast suffer heavy rains and floods each year from the remnants of hurricanes spawned off Mexico.
• Islands, such as Hawaii, Guam, American Samoa, and Puerto Rico are also vulnerable to hurricanes. During 1993, Guam suffered by five typhoons. Hurricane Iniki struck the island of Kauai, Hawaii, on September 11, 1992, resulting in $1.8 billion damage.
| RANKING | HURRICANE | YEAR | CATEGORY | DAMAGE (U.S.) |
|---|---|---|---|---|
| 1. | ANDREW (SE FL/SE LA) | 1992 | 4 | $26,500,000,000 |
| 2. | HUGO (SC) | 1989 | 4 | $7,000,000,000 |
| 3. | FRAN (NC) | 1996 | 3 | $3,200,000,000 |
| 4. | OPAL (NW FL/AL) | 1995 | 3 | $3,000,000,000 |
| 5. | FREDERIC (AL/MS) | 1979 | 3 | $2,300,000,000 |
| 6. | AGNES (NE U.S.) | 1972 | 1 | $2,100,000,000 |
| 7. | ALICIA (N TX) | 1983 | 3 | $2,000,000,000 |
| 8. | BOB (NC and NE U.S.) | 1991 | 2 | $1,500,000,000 |
| 8. | JUAN (LA) | 1985 | 1 | $1,500,000,000 |
| 10. | CAMILLE (MS/AL) | 1969 | 5 | $1,420,700,000 |
This information is taken fromThe National Oceanic and Atmospheric Administration'sThe Deadliest, Costliest, and Most Intense United States hurricanes of this century (and other frequently requested hurricane facts) [NOAA Technical Memorandum NWS TPC-1] updated in February, 1997.
If you would like more information aboutHurricanes, Typhoons and Tropical Cyclones, please visit these resources.
An extensive list ofQuestions and Answers about Hurricanesby Dr. Chris Landsea.
Climate
Prediction Center
The mission of the Climate Prediction Center is to maintain a continuous watch on
short-term climate fluctuations and to diagnose and predict them. These efforts are
designed to assist agencies both inside and outside the federal government in coping with
such climate related problems as food supply, energy allocation, and water resources.
Hail Size and Wind Speed Tables
From National Weather Service Pleasant Hill (MO).
Hurricanes: A Preparedness Guide
InteractiveNational Map of Watches and Warningsfrom Texas A&M.
Latest advisories from the National Hurricane Center-- Atlantic and East Pacific.
Latest
Weather Warnings Across the Country
From National Weather Service IWIN page.
National Severe Storms
Laboratory
Scientific research into severe and hazardous weather.
Severe
and Unusual Weather Terminology
A glossary of some technical meteorological terms.
Storm Prediction
Center
SPC monitors and forecasts severe and non-severe thunderstorms, tornadoes, and
other hazardous weather phenomena across the conterminous U.S. -- 24 hours a day, every
day of the year. They used to be known as the SEvere Local Storms (SELS) unit of the
National Severe Storms Forecast Center (NSSFC).
Storm Track
Non-profit magazine devoted to severe storms.
Hurricanes, Typhoons and
Tropical Cyclones