Hurricane Allen Explained

Formed:July 31, 1980
Dissipated:August 11, 1980
Winds:165
Pressure:899
Year:1980
Fatalities:269
Missing:25
Damage:1570000000
Areas:Lesser Antilles, Puerto Rico, Haiti, Jamaica, Cayman Islands, Yucatán Peninsula, Northern Mexico, Southern Texas
Season:1980 Atlantic hurricane season

Hurricane Allen was the strongest Atlantic hurricane by wind speed on record. An extremely powerful tropical cyclone, Allen affected the Caribbean, eastern and northern Mexico, and South Texas in August 1980. The second tropical depression, first named storm, and first hurricane of the 1980 Atlantic hurricane season, Allen was the sixth most intense Atlantic hurricane on record in terms of barometric pressure. It was one of the few hurricanes to reach Category 5 status on the Saffir–Simpson scale on three occasions, and spent more time at Category 5 status than all but two other Atlantic hurricanes. Allen is the only hurricane in the recorded history of the Atlantic basin to achieve sustained winds of 190 mph (305 km/h),[1] Until Hurricane Patricia in 2015, these were also the highest sustained winds in the Western Hemisphere. Hurricane Allen was also the third strongest tropical cyclone to exist in the Gulf of Mexico in terms of pressure, behind hurricanes Milton and Rita.

Throughout its life, Allen moved through the deep tropics on a westerly to northwesterly course through the tropical Atlantic Ocean, Caribbean Sea, and Gulf of Mexico before making its final landfall near the United States–Mexico border. At peak strength, it passed near Haiti, causing hundreds of deaths and heavy damage. After crossing the Gulf of Mexico, Allen weakened as it struck the lower Texas coast, causing high winds, a significant storm surge, and heavy rainfall, which caused damage to South Texas. Overall, Allen killed at least 269 people and left $1.57 billion in damages (1980 US dollars), mostly within Haiti and the United States. Due to the hurricane's impact, the name Allen was retired from the six-year revolving list of Atlantic tropical cyclone names in 1981 and replaced by Andrew. The remnants of the storm caused a brief lapse in the heat wave of 1980 in places like Dallas/Fort Worth, Texas, which had recorded 69 days of 100F heat.

Meteorological history

Allen was an early-season Cape Verde-type hurricane, originating from a tropical wave that left the African coastline on July 30. The system developed quickly as it moved westward, becoming a tropical depression the following day. However, the National Hurricane Center did not initiate advisories on Allen until almost 24 hours later, when it was centered 1300miles east of the Windward Islands.[2] Early on August 2, as the depression moved quickly westward towards the Caribbean, it intensified into the first named storm of the 1980 Atlantic hurricane season. Allen rapidly strengthened as it continued westward. By the time an aircraft reconnaissance plane entered the tropical cyclone's center late on August 3, it had already achieved major hurricane status, with maximum sustained winds of and a minimum central pressure of, making Allen a Category 3 hurricane. The storm's central pressure dropped to that night as its eye passed north of Barbados on August 4.

Allen continued to move quickly westward and entered the Caribbean Sea shortly after passing south of St. Lucia. Allen's rapid intensification continued during this time, as it was steered by a mid- to upper-level ridge to its north. Shortly before 0000 UTC on August 5, the hurricane's minimum pressure decreased to 924mbar, which was noted as equivalent to Hurricane David in the previous season.[3] Another reconnaissance aircraft shortly thereafter discovered Allen had become an extremely strong Category 5 hurricane, with sustained winds of and a minimum pressure of the following day. This was the lowest central pressure ever recorded in the eastern Caribbean Sea.[4] Allen maintained its extreme intensity for most of the day. However, late on August 5, the storm began to weaken as it underwent an eyewall replacement cycle and interacted with the mountainous terrain of Hispaniola, with the storm taking a northwestward jog south of the island, a common track deviation for most hurricanes that have passed through the area.[4] [5]

Allen resumed a more westward course as it left behind Hispaniola and passed north of Jamaica and the Cayman Islands on August 6. The very warm waters of the northwestern Caribbean Sea allowed the storm to begin another phase of rapid intensification. Allen reached its second and greatest peak intensity on the afternoon of August 7, with maximum sustained winds of and a minimum barometric pressure of .[5] Allen had the highest maximum sustained winds ever recorded in an Atlantic hurricane. Its minimum pressure of 899 millibars was the second-lowest pressure on record for the basin at the time. The major hurricane was also very large at this time, with hurricane-force winds extending from its center and tropical-storm-force winds extending 345 miles.[4] Allen's circulation filled nearly the entire Gulf of Mexico, and was regarded at the time as the second-largest Atlantic hurricane on record, after 1961's Hurricane Carla. Continuing westward, the southern portion of Allen's circulation passed over the Yucatán Peninsula, causing the cyclone to weaken again. Allen bottomed out with winds of on August 8.[4] Continued movement west over the warm waters of the Gulf of Mexico allowed Allen to restrengthen into a Category 5 hurricane for a third time as it moved over the open waters of the Gulf. The hurricane's central pressure dropped back to a tertiary low of 909mbar. Pressure falls over the southern United States at this time indicated Allen would soon slow its forward motion as it approached Texas. Allen's forward speed slowed considerably in the hours before it made landfall near Brownsville as a low-end Category 3 major hurricane on August 10. The storm rapidly weakened as it moved inland, eventually dissipating over the mountainous terrain of northern Mexico the following day.[5]

Preparations

As Allen approached the Caribbean Sea, gale warnings and a hurricane watch were issued for the islands of Barbados, St. Lucia, St. Vincent, Dominica, Grenada, Martinique, and Guadeloupe during the daylight hours of August 3. Gale warnings were in effect for Antigua from 11 am on August 3 until 11 am on August 4. Hurricane warnings were raised for Barbados, St. Vincent, St. Lucia, Martinique, and Dominica from the early afternoon of August 3 until the late morning of August 4. As Allen moved into the Caribbean sea, hurricane watches were issued for southeastern sections of the Dominican Republic and the southwestern peninsula of Haiti from 11 am on August 4 until the morning of August 5. Gale warnings were then in effect for the southern Dominican Republic from the night of August 4 into the night of August 5, while southern Haiti maintained the warnings from the night of August 4 into the morning of August 5. The hurricane watch was issued for Jamaica during the morning hours of August 5, while hurricane warnings were raised for the southwest peninsula of Haiti from the late morning of August 5 into the morning of August 6.[6] Hurricane warnings went into effect for Jamaica from around noon on August 5 until late in the afternoon of August 6. The Cayman Islands saw hurricane watches issued from the afternoon of August 5 into the morning of August 6 before the watches were upgraded to hurricane warnings from the morning until late afternoon of August 6.

As Allen approached the Gulf of Mexico, hurricane warnings were raised for the northeast Yucatán peninsula of Mexico from the afternoon of August 6 into the morning of August 8. Gale warnings were in effect for the Florida Keys from the evening of August 6 into the early morning of August 8. As Allen approached its final landfall, the northeast Mexican coast and Texas coast were placed under a hurricane watch from the morning of August 8 until the morning of August 9 for Mexico and the afternoon of August 9 for Texas. Hurricane warnings were posted for the Texas coast during the afternoon of August 8, and were lowered north of Freeport, Texas during the afternoon of August 9 and south of Freeport during the afternoon of August 10. Gale warnings and a hurricane watch were issued for the Louisiana coast from Vermilion Bay westward from the afternoon of August 8 into the afternoon of August 9. Hurricane warnings were in effect for northeast Mexico from the early afternoon of August 9 into the late afternoon of August 10. Hurricane warnings were downgraded to gale warnings between High Island, Texas and Freeport, Texas between the late afternoon of August 9 and the late afternoon of August 10. Hurricane watches were dropped for the Louisiana coast during the late afternoon of August 9. Hurricane warnings were downgraded to gale warnings for the lower Texas coast south of Freeport from the late afternoon of August 10 into the early morning of August 11.[7]

In addition to the various watches and warnings put in place ahead of Allen's arrival, various international governments took measures to prepare for the hurricane in Haiti. A disaster committee and executive committee to address the aftermath of the storm was formed by Haitian President Jean-Claude Duvalier, the latter of which was headed by members of the Haitian Ministry of Health and Hatian Red Cross, while members of the committees included representatives from the army, Pan American Health Organization (PAHO), United States Agency for International Development (USAID), and others. Emergency instructions were issued by the Haitian government to prevent possible increases in malaria cases following Allen's passage. The United States government made preparations to send personnel, as well as financial and aerial assistance, to Haiti.[8]

Tens of thousands of people evacuated the Texas coast before Allen's landfall, and forecasters advised that all areas within one mile of the coastline be cleared. The American Red Cross opened 109 shelters across Hidalgo County and in the city of Corpus Christi.[9] Access to Padre Island National Seashore was cut off, and all visitors there and residents of Galveston Island were ordered to evacuate the respective areas. Six thousand people in lower Cameron Parish, Louisiana, 14,000 people in Port Lavaca, and additional residents of the low-lying suburbs of Houston, Texas were ordered to evacuate as well. A total of 2,500 troops were put on alert in Texas prior to the storm's passage.[9] [10]

Impact

Deaths and damage by area
Country Deaths Damage Source
Barbados None [11]
Cayman Islands None [12]
Cuba 3
Dominican Republic
Grenada None
Guadeloupe Unknown
Haiti [13]
Jamaica
Martinique None
Mexico None None
St. Lucia
St Vincent and The Grenadines None
United States [14]
Offshore
Total
Allen caused just over $1 billion (1980 USD) in damages and killed at least 269 people throughout its course (including indirect deaths).[12] [13]

Caribbean

In Barbados, damages were estimated to be $6 million (1980 USD) by local officials, mostly to agriculture, housing and the local fishing industry. The highest recorded winds on the island were 68 knots on its south side, though Allen likely brought much stronger winds of greater than 100 knots on the northern part of Barbados under the eyewall of the hurricane. About 500 houses were either damaged or destroyed. No deaths were reported. 20 small boats were destroyed on the island and another 75 sustained damage. The island of St. Lucia sustained catastrophic damage from Allen when it was a strong category 3 hurricane. Sustained winds of 90kn and a sea level pressure as low as 967mbar were reported at Hewanorra. A total of $235 million in damage was incurred on the island.[15] The country's banana crop was devastated, and its main hospital, Victoria Hopsital, was left powerless and with part of its roof missing. Much of St. Lucia's telephone lines and other communications were down due to the storm, and foreign governments communicated with the island via ham radio.[16] Eighteen people lost their lives as a result of the storm's passage. One death in Guadeloupe was attributed to Allen.[12] In Martinique, damage was extensive as the storm passed 50miles south of the island. Waves 6m (20feet) high battered the coast of the island during the storm.[17] Torrential rainfall caused damage to agriculture on Saint Vincent. Despite being located away from Allen's center as it passed to the south, Puerto Rico saw wind gusts of up to due to the hurricane.

In the central Caribbean, Cayman Brac was hit by winds in excess of 115mi/h which caused considerable property damage. A coral reef at Discovery Bay, Jamaica was devastated by the wave action from the storm.[18] Offshore Jamaica, greater numbers of smaller-sized Damselfishes was witnessed in the wake of Allen.[19] Storm surge and strong waves along Jamaica's northeastern coast damaged buildings, and 10inches to 20inches inches of rainfall was recorded. Eight deaths in Jamaica occurred due to Allen. Three additional deaths were attributed to Allen in Cuba.[13]

Extensive damage occurred in Haiti due to high winds and flash flooding. Total costs for that country were estimated to be at more than $400 million (1980 USD). 2.5 million people were affected by the storm, with an estimated 333,000 people considered at risk for food shortage.[8] Roughly 60% of the nation's coffee crop was destroyed. In Port-au-Prince, Allen caused many fallen trees, local flooding, and temporary disruptions to electric power and telephone services.[8] 41 deaths were caused by tin roofs flying off homes and around 1,200 became homeless due to the flooding.[20] The island of Île-à-Vache had its food supply depleted and its entire water supply contaminated with salt water. [8] Another 140 people were reported dead from flooding.[21] In all, 220 people were killed and 835,000 were left homeless by catastrophic flooding and wind damage from Allen.

United States

In Texas, the storm surge was reported as high as 12feet at Port Mansfield, though it may have been higher elsewhere along the Texas coast. A peak wind gust of 129mi/h was also measured at Port Mansfield. Tropical storm-force winds in Corpus Christi, Texas blew roof gravel through the city, which led to substantial glass breakage to the 18-story Guarantee Bank Building and a 12-story wing of Spohn hospital.[22] Allen dumped 15inchesto20inchesin (toin) of rain in south Texas along a 50 to 100 mile swath of land from the coast inland, ending a summer-long drought during the Heat Wave of 1980.[23]

The storm caused seven 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; a total of 29 were reported in association with the hurricane. One tornado caused $100 million in damage when it hit Austin, Texas, making it the costliest tropical cyclone-spawned tornado in recorded history. Two offshore oil rigs in the Gulf of Mexico were destroyed by Allen, and 13 people died in the aforementioned helicopter crash during the evacuation of a rig. A total of $300 million in damage was recorded in Texas due to Allen. Overall, however, the storm caused less damage than initially feared in the United States due to its suddenly diminished power, as well as its highest tides and winds hitting a sparsely populated portion of the Texas coast.[13] [24]

Elsewhere

Areas of northeastern Mexico saw heavy rains with the passage of Allen, with the highest totals exceeding 7inches.[25] The hurricane earlier brushed the Yucatán Peninsula. As Allen only affected sparsely populated regions of Mexico, there were no reports of significant damage.[13]

The Panamanian freighter Georgios G went missing on August 5 on the way to Belize City with 25 people on board. While information on the ship's fate is incomplete, it was likely intercepted by Allen on its course.

Retirement

See also: List of retired Atlantic hurricane names. Because of the hurricane's destructive impacts, the name Allen was retired from the Atlantic tropical storm name list by the World Meteorological Organization in the spring of 1981, and will never again be used for a future Atlantic hurricane.[26] It was replaced with Andrew for the 1986 season.[27] [28]

See also

Notes

Further reading

External links

Notes and References

  1. All wind speeds in the article are maximum sustained winds sustained for one minute, unless otherwise noted.
  2. Web site: Tropical Depression Advisory Number 1. Gilbert Clark. August 1, 1980. National Hurricane Center. May 13, 2011.
  3. Web site: Discussion for Hurricane Allen, 5 p.m. EDT, August 4, 1980. Miles Lawrence. August 4, 1980. National Hurricane Center. May 13, 2011.
  4. Web site: Hurricane Allen July 31-August 11, 1980. Donovan Landreneau. National Oceanic and Atmospheric Administration. November 26, 2024.
  5. News: 1980 Allen-NHC Report. National Hurricane Center. November 26, 2024.
  6. Web site: National Hurricane Center. Hurricane Allen Tropical Cyclone Report Page 3. National Oceanic and Atmospheric Administration. 1980. February 16, 2010. National Hurricane Center.
  7. Web site: National Hurricane Center. Hurricane Allen Tropical Cyclone Report Page 4. National Oceanic and Atmospheric Administration. 1980. February 16, 2010. National Hurricane Center.
  8. Disaster Case Report:Haiti - Hurricane Allen. Office of Foreign Disaster Assistance. August 5, 1980. November 26, 2024.
  9. Killer Hurricane Heads for Area of Texas Coast. The Press-Courier. August 9, 1980. November 27, 2024.
  10. Texans flee before rampaging Allen. The Morning Record and Journal. August 9, 1980. November 27, 2024.
  11. Lawrence, Miles B. Pelissier, Joseph M. Atlantic Hurricane Season of 1980. Monthly Weather Review. July 1, 1981. 109. 7. 1567–1582. 10.1175/1520-0493(1981)109<1567:AHSO>2.0.CO;2. American Meteorological Society. 1981MWRv..109.1567L . free.
  12. Hurricane Allen Tropical Cyclone Report Page 5. National Hurricane Center. National Oceanic and Atmospheric Administration. December 6, 2012.
  13. Web site: Hurricane Allen Tropical Cyclone Report Page 6. National Hurricane Center. National Oceanic and Atmospheric Administration. December 14, 2008.
  14. National Hurricane Center . Hebert, Paul J . Taylor, Glenn . September 24, 2012 . live . January 1983 . The Deadliest, Costliest, and Most Intense United States Hurricanes of This Century (and Other Frequently Requested Hurricane Facts) . NOAA Technical Memorandum NWS TPC-18 . December 2, 2012 . https://web.archive.org/web/20120924061413/http://www.aoml.noaa.gov/general/lib/lib1/nhclib/nwstechmemos/techmemo18.pdf . United States National Oceanic and Atmospheric Administration's National Weather Service . 5 .
  15. Atlantic Hurricane Season of 1980. American Meteorological Society. Monthly Weather Review. Miles B. Lawrence . Joseph M. Pellisier . 109. 7. 1567–1572. July 1981. February 17, 2010. 1981MWRv..109.1567L. 10.1175/1520-0493(1981)109<1567:AHSO>2.0.CO;2.
  16. Hurricane Allen zeroes in on Jamaica. The Telegraph. Associated Press. August 5, 1980. December 2, 2024.
  17. 4300098. Journal of Coastal Research. 15. 877–899. Trade Wind Intensification and Hurricanes on a Caribbean Beach, Martinique Island: A Comparison of their Morphological Effects From Field Experiments and Numerical Simulations. K. Bosser . F. Levoy . J. C. Flageollet . O. Monfort . H. Rousset . Summer 2000. Coastal Education & Research Foundation, Inc.. 3.
  18. Web site: Hurricane Hugo's Impact on Salt River Submarine Canyon, St. Croix, U.S. Virgin Islands. Richard B. Aronson . Kenneth P. Sebens . John P. Ebersole . February 16, 2010. Atlantic Oceanographic and Meteorological Laboratory. 2003.
  19. Pre- and post-hurricane assessment of artificial reefs: evidence for potential use as refugia in a fishery management strategy. Robert K. Turpin . Stephen A. Bortone . ICES Journal of Marine Science. 59. S75. 2002. 10.1006/jmsc.2002.1191. free. 2002ICJMS..59S..74T .
  20. Jim Williams (2010). Port au prince, Haiti's history with tropical systems. Hurricanecity.com. Retrieved February 17, 2010.
  21. News: Allen Leaves Flooding In Its Wake; 140 New Deaths Reported. Associated Press. Saint Petersburg Times. August 12, 1980. February 29, 2012.
  22. Effects of Hurricane Allen on Buildings and Coastal Construction . Joseph E. . Minor P.E. . William L. Beason . Timothy P. Marshall . Fourth National Conference on Wind Engineering Research . 1981 . February 16, 2010 . dead . https://web.archive.org/web/20140103233849/http://www.depts.ttu.edu/nwi/Pubs/Reports/D8-10-80%20Hurr%20Allen.pdf . January 3, 2014 .
  23. Web site: Hurricane Allen. David M. Roth. Hydrometeorological Prediction Center. January 27, 2007. February 16, 2010.
  24. News: Allen Floods Texas, Fizzles Over Mexico. Associated Press. Pittsburgh Post-Gazette. August 12, 1980. February 29, 2012.
  25. Web site: David M. Roth. Storm Total Rainfall From Hurricane Allen (1980). January 15, 2007. February 16, 2010. Hydrometeorological Prediction Center.
  26. Web site: Tropical Cyclone Naming History and Retired Names. National Hurricane Center. Miami, Florida. April 5, 2024.
  27. National Hurricane Operations Plan. 37. NOAA Office of the Federal Coordinator for Meteorological Services and Supporting Research. Washington, D.C.. May 1986. April 5, 2024.
  28. News: Andrew, Agatha, top 1986 list. May 23, 1986. The Gadsden Times. Gadsden, Alabama. Associated Press. April 5, 2024.