HURRICANE ALLEN

'Hurricane Allen' was the strongest hurricane of the 1980 Atlantic hurricane season. It was one of the strongest hurricanes in recorded history, one of the few hurricanes to reach Category 5 status on the Saffir-Simpson Hurricane Scale on three separate occasions, and spent more time as a Category 5 than any other Atlantic hurricane. Allen is one of only two recorded hurricanes in the Atlantic to achieve 190 mph sustained winds, the other being Hurricane Camille.

Contents

Storm history

Records

Impact

Lesser Antilles

Haiti

Jamaica

Cuba

Cayman Islands

United States

Retirement

References

See also

External links

Storm history

Allen originated as a Cape Verde-type hurricane, a rarity for tropical systems in early August. The tropical disturbance which would become Allen moved off the coast of Africa on July 30, and was upgraded to a tropical depression on August 1. Early on August 2, as it moved towards the Caribbean it became the first named storm of the season. Allen moved westward at an unusually high speed of 15 to 20 knots, rapidly intensifying into a Category 5 hurricane at 0000 (GMT) on August 5 while south of Puerto Rico and (very unusually) remaining so for over a day. During this time Allen attained a central pressure of 911mb, the lowest pressure on record in the Eastern Caribbean. The eye passed just south of Hispaniola and just north of Jamaica as a Category 4 hurricane.³
After weakening from interactions with the mountains of Haiti and Jamaica, Allen reintensified to a Category 5 for a second time, again retaining this intensity for over a day. It moved between Cuba and the Yucatán Peninsula, reaching its minimum pressure of 899mb while crossing the Yucatán Channel. Interestingly, during Allen's trek through the Caribbean Sea and the Gulf of Mexico, its center of circulation never crossed over land despite its close passage to the islands of the Caribbean.³

Allen again weakened to a Category 4 storm through interactions with land, but it restrengthened into a Category 5 hurricane for a third time as it moved over the warm waters of the Gulf of Mexico, again keeping this intensity for nearly a full day and with a pressure drop to 909mb, the lowest pressure ever recorded in the western Gulf of Mexico. Shortly before landfall, dry air aloft in the Gulf caused the massive storm to weaken substantially. Allen made landfall north of Brownsville, Texas as a Category 3 storm with sustained winds of only 115 mph.³

Records

When Allen reached Category 5 intensity on August 5, it became the earliest Category 5 storm ever recorded. This record stood until Hurricane Emily shattered it on July 16, 2005.

Allen is one of the few Atlantic hurricanes to reach Category 5 on the Saffir-Simpson hurricane scale on three separate occasions, the others being Hurricane Ivan and Hurricane Isabel.
Allen also produced the fifth-lowest minimum pressure ever recorded in the Atlantic basin at 899 mbar (hPa) and was the strongest known hurricane in the basin, in terms of pressure, since 1935.^[1] It remains the most intense storm ever in August.
Allen spent nearly 3 days as a Category 5 storm, by far the highest of any Atlantic hurricane.

Impact

Storm deaths by region
(incomplete)

Region	Deaths[2]
Haiti	220
United States	24
St. Lucia	18
Jamaica	8
Cuba	3
Guadeloupe	1
Total (direct & indirect)	274

Allen caused $2.6 billion (2005 USD) in damages and killed at least 274 people throughout its course (including indirect deaths).^[3]

Lesser Antilles

Preliminary damages for Barbados were estimated to be $1.5 million (1980 USD). About 500 houses were either damaged or destroyed. No deaths were reported. St. Lucia sustained heavy damage from Allen. Eighteen people lost their lives as a result of the storm's passage. One death in Guadeloupe was attributed to Allen.

Haiti

Extensive damage occurred due to high winds and flash flooding. Total costs were estimated to be at more than $400 million (1980 USD). Roughly 50% of the nation's coffee crop was destroyed. In all, 220 people were killed and 835'000 were left homeless. In the capital Port-au-Prince, 41 deaths were caused by tin roofs flying off and around 1200 were made homeless by flooding ^[4].

Jamaica

In Jamaica, 8 deaths were attributed to Allen. Damage was very significant along the northeast coast, where the hurricane made its closest approach to the island.

Cuba

There were no reports of significant damage, though 3 deaths were attributed to Allen.

Cayman Islands

Cayman Brac was hit by winds in excess of 115 mph which caused considerable property damage. No deaths were reported.

United States

In Texas, the storm surge was reported as high as 12 feet at Port Mansfield, though it may have been higher because the highest surges occurred in unpopulated and unmonitored sections of the Texas coast. A peak wind gust of 129 mph was also measured at Port Mansfield. The storm caused 7 deaths in Texas and 17 in Louisiana (most resulting from the crash of a helicopter evacuating workers from an offshore platform). Allen spawned several tornadoes in Texas. One tornado caused $100 million in damage when it hit Austin, Texas, making it the costliest tropical cyclone-spawned tornado ever. Overall, however, the storm caused limited damage in the United States due to its suddenly diminished power and because its highest tides and winds hit a sparsely-populated portion of the Texas coast.³
One bit of good news resulted from Allen's arrival -- it dumped 10 to 20 inches of rain in south Texas, ending a summer-long drought during the Heat Wave of 1980. Its storm total rainfall map is shown to the right.^[5]

Retirement

The name Allen was retired from the Atlantic tropic storms list in the spring of 1981, and will not be used for a future Atlantic hurricane. It was replaced with Andrew in the 1986 season.

References

1. NOAA. Hurricane Katrina Service Assessment. Retrieved on 2007-04-13.
2. Preliminary Storm Report. Hurricane Allen. Retrieved on 2007-04-13.
3. Hurricane Allen Tropical Cyclone Report
4. Hurricanecity. Port au prince,Haiti's history with tropical systems. Retrieved on 2007-04-13.
5. "NOAA HPC - Hurricane Allen"

See also

★ List of notable tropical cyclones

★ List of notable Atlantic hurricanes

★ List of Category 5 Atlantic hurricanes

External links

★ National Weather Service - Hurricane Allen

★ The Wake of Hurricane Allen in the Western Gulf of Mexico

★ Effects of Hurricane Allen on Buildings and Coastal Construction

★ Pertinent Meteorological Data for Hurricane Allen of 1980