Tropical Storm Alma (1974) Explained

Tropical Storm Alma
Formed:August 12, 1974
Dissipated:August 15, 1974
Winds:55
Pressure:1007
Year:1974
Fatalities:51 total
Damage:5000000
Areas:Trinidad and Tobago, Venezuela
Season:1974 Atlantic hurricane season

Tropical Storm Alma, the first named storm to develop in the 1974 Atlantic hurricane season, was a short lived tropical cyclone that made a rare Venezuelan landfall. The storm formed from the Intertropical Convergence Zone (ITCZ) on August 12 well to the east of the Windward Islands, but advisories were not issued until the next day when Alma was at peak intensity. Alma entered the southeastern Caribbean Sea at an unusually brisk westward pace of between 20mi/h to 25mi/h, prompting numerous watches and gale warnings throughout the nations in this region. After crossing Trinidad, Alma became one of only four tropical storms to traverse the Paria Peninsula of northeastern Venezuela. The storm dissipated on August 15 over the high terrain of Venezuela.

Alma left heavy damage in Trinidad, amounting to about US$5 million (value in 1974), making it the most destructive cyclone of the 20th century on the island at that time. Alma damaged about 5,000 buildings, leaving 500 people homeless. The storm also wrecked 17750acres of crop fields. There were two deaths in Trinidad, including one person who was struck by flying debris. Alma's heavy rainfall was responsible for a plane crash on Isla Margarita off the Venezuelan coast, killing the 49 people on board.

Meteorological history

A disturbance associated with the Intertropical Convergence Zone (ITCZ) left the coast of West Africa on August 9,[1] producing mid-level winds of 75 mph (120 km/h) in Dakar, Senegal.[2] A weak circulation formed near the sea surface on August 10 within an area of thunderstorms.[3] The disturbance moved slowly westward over the Atlantic Ocean, developing into a tropical depression at 18:00 UTC on August 12, around the 10th parallel north,[2] an unusually southern latitude the cyclone would remain around throughout its lifetime. On August 13, the depression intensified into Tropical Storm Alma about 375 mi (605 km) east of Trinidad and Tobago, as indicated by a Hurricane Hunters flight reporting winds of 65 mph (105 km/h).[2] This same flight observed a circular eye with a diameter of 36miles, the only report of an eye-like structure from this storm.[4]

The center of Alma was elongated, causing gale-force winds to extend 75 mi (120 km) to the north while extending only 25miles to the south.[5] On August 14 the Hurricane Hunters measured gusts of 80 mph (130 km/h); however, the storm's overall wind pattern weakened after its initial peak.[2] Alma continued westward at 23mph, which National Hurricane Center (NHC) Director Neil Frank noted was unusually rapid for a tropical cyclone at this time and location.[5] Alma was able to maintain its low latitude westward movement due to a strong subtropical ridge to its north, which was at an unseasonably low latitude for the month of August.[1]

On August 14, Alma made landfall on Trinidad with winds of 55 mph (90 km/h),[6] the southernmost landfall on that island since a storm in 1933.[1] Even though the storm traversed Trinidad in only three hours,[7] its time over land was sufficient to disrupt the circulation.[8] The storm crossed the Gulf of Paria and made its second and final landfall on the Paria Peninsula of Venezuela,[7] one of only four storms on record to do so; the others were in 1605, 1725, and 1933. The high mountains in Venezuela took a toll on the storm, ripping the circulation and causing Alma to be downgraded to a tropical depression on August 15.[2] At 02:00 UTC that day, Alma's circulation passed near Caracas. The convection rapidly diminished, and the storm's presence on satellite imagery faded, though the NHC noted the potential for redevelopment once it reached open waters.[9] The storm did not survive its trek over land; late on August 15, the NHC issued the final advisory after the circulation dissipated near the border of Venezuela and Colombia.[10] The remnants of Alma continued westward across South and Central America, reaching the Pacific Ocean where they would eventually restrengthen into Hurricane Joyce.[11]

Preparations, impact, and aftermath

Before Alma made landfall, gale warnings and a hurricane watch was issued for Trinidad, Tobago, Grenada, Saint Vincent and the Grenadines, and Barbados. As Alma progressed westward, gale warnings were also issued for the Paria and Paraguaná peninsulas of Venezuela, the Guajira Peninsula, and the ABC islands.[2] Initially, the Trinidad and Tobago weather service anticipated Alma would strike Tobago, but as the storm approached, the trajectory over Trinidad became apparent.

While moving across Trinidad, Alma produced sustained winds of only 35 mph (56 km/h) at Piarco,[2] yet gusts reached 91 mph (147 km/h) at Savonetta.[12] Rainfall at Piarco did not exceed 1 inch (25 mm) during the storm's passage.[13] The strong gusts downed trees and power lines,[8] and damaged about 5,000 buildings, including schools, hospitals, and hundreds of households, wrecking everything inside. This left about 500 people homeless.[14] Alma also caused widespread damage to agriculture, mostly to sugar, resulting in 17750acres of ruined fields. Several highways in the country suffered damage.[14] The winds flung debris from a roof, which struck and killed a woman.[8] There was also an indirect death on the island,[12] along with several injuries.[15] Damage estimates on the island totaled $5 million (1974 USD);[16] the American embassy in the country considered Alma to be the most destructive storm in Trinidad during the 20th century.[17]

After the storm, local Red Cross volunteers provided meals and clothing to thousands of storm victims. The government allocated $5.1 million (Trinidad and Tobago dollars) for relief work, to be coordinated by the National Emergency Relief Organization of Trinidad and Tobago, which was established following the damaging Hurricane Flora in 1963. This helped rebuild damage houses, clear roads, and assist affected farmers. The United States Agency for International Development sent about US$5,000 in assistance, after the country's ambassador sent a formal request to Washington, D.C. The Amoco oil company also sent a $500 donation to the country's Red Cross.[14]

While moving through the Windward Islands, Alma produced strong wind gusts on Grenada.[18] The outer rainbands of Alma spread over Venezuela while the center was still over Trinidad.[2] At about 13:00 UTC on August 14, the rains caused a Linea Aeropostal Venezolana Vickers Viscount 749 turboprop airliner circling the airport on Isla Margarita to crash.[19] The aircraft struck the side of La Gloria, 26abbr=onNaNabbr=on below the summit. All but one of the 49 people aboard died on impact; the co-pilot survived for 17 more days before dying from irreversible brain damage.[20] Elsewhere in Venezuela, Alma's heavy rainfall triggered several landslides.[21]

See also

Notes and References

  1. John R. Hope. 1975. Atlantic Hurricane Season of 1974. Monthly Weather Review. 103. 4. 285–293. 10.1175/1520-0493(1975)103<0285:AHSO>2.0.CO;2. 1975MWRv..103..285H. 1520-0493. free.
  2. Web site: National Hurricane Center. Paul J. Hebert. 1974-08-26. Tropical Storm Alma Tropical Cyclone Report. 2008-01-05.
  3. Helmut K. Weickmann . Alexis B. Long . L. Ray Hoxit . amp . 1977. Some Examples of Rapidly Growing Oceanic Cumulonimbus Clouds. Monthly Weather Review . 105 . 4 . 469–476 . 10.1175/1520-0493(1977)105<0469:SEORGO>2.0.CO;2 . 1977MWRv..105..469W . 1520-0493 . free .
  4. Web site: John R. Hope and Staff. 1976. Annual Data and Verification Tabulation of Atlantic Cyclones 1974. 2008-01-08.
  5. News: 1974-08-14. First Tropical Storm Brews off Trinidad. United Press International. Bangor Daily News. 2014-03-15.
  6. News: 1974-08-14. Storm Alma Hits Trinidad; Warnings Out. Spokane Daily Chronicle. 2014-08-15. Associated Press.
  7. News: 1974-08-15. Storm Crashes in Storm. Bangor Daily News. 2014-03-15.
  8. News: Daytona Beach Morning Journal. Associated Press. 1974-08-15. Alma Hits Trinidad, Kills One. 2014-03-15.
  9. Paul J. Hebert. Tropical Storm Alma Tropical Cyclone Discussion. 1974-08-15. 2014-03-15. JPG.
  10. Miles B. Lawrence. Tropical Disturbance Alma Tropical Cyclone Discussion. 1974-08-15. 2014-03-15. JPG.
  11. Neil Frank. 1974. Atlantic Tropical Systems of 1974. Monthly Weather Review. 103. 4. 294–300. 10.1175/1520-0493(1975)103<0294:ATSO>2.0.CO;2. 1975MWRv..103..294F . 1520-0493. free.
  12. Tropical Cyclones Affecting Trinidad and Tobago 1725-2000 . Trinidad and Tobago Meteorological Service via the Internet Wayback Machine . 2002-05-02 . 2011-10-13 . unfit . https://web.archive.org/web/20051223215859/http://nema.gov.tt/resources/downloads/tropicalcyclones.pdf . December 23, 2005 .
  13. José A. Colón. 1974-08-21. Report on Tropical Storm Alma. San Juan Weather Service Forecast Office. National Hurricane Center. 2014-03-15. PDF.
  14. United States Agency for International Development. Trinidad and Tobago - Tropical Storm Case Report. 2014-03-16.
  15. News: The Telegraph. 1974-08-15. Tropical Storm Alma Blamed for Plane Crash; 47 Killed. 2014-03-15. United Press International.
  16. Web site: Office of U.S. Foreign Disaster Assistance. Significant Data on Major Disasters Worldwide 1900-present. August 1993. 2014-03-15.
  17. National Hurricane Center. American Embassy at Port of Spain. 1974-08-30. USG Disaster Assistance for Relief of Victims of Tropical Storm Alma in Trinidad. 2014-03-16. JPG.
  18. News: The Day. 1974-08-13. Tropical Storm Alma Roars into Trinidad. 2014-03-13. Associated Press.
  19. News: United Press International. The Telegraph. 1974-08-15. 2011-07-30. Tropical Storm Alma Blamed For Plane Crash; 47 Killed. 8.
  20. Web site: Aviation Safety Network. 2007-02-12. 2011-07-30. Aircraft Accident: Vickers 749 Viscount YV-C-AMX Isla Margarita.
  21. José A. Colón. 1974-08-21. Report on Tropical Storm Alma. San Juan Weather Service Forecast Office. National Hurricane Center. 2014-03-15. 2. PDF.