Tropical Storm Alma was the first named storm of the 2008 Pacific hurricane season. Alma had its origins within a trough that had draped itself across the Gulf of Tehuantepec in late May, generating a widespread area of convection across the southwestern Caribbean and adjacent eastern Pacific. Alma developed on May 29 while located a short distance southwest of Costa Rica. Alma moved north, then northwest and made landfall that same day near Leon, Nicaragua as a 65 mph tropical storm. Alma quickly dissipated after landfall, but not before triggering torrential rainfall and associated floods and mudslides across portions of Central America.
Alma formed the farthest east out of any East Pacific tropical cyclone on record, though it was not the first to impact the Pacific side of Central America; Tropical Storm Andres in the 1997 season also struck the same general area, as did Hurricane Adrian in 2005.
Alma's mid-level remnants combined with a westward-moving tropical wave over the western Caribbean to trigger the genesis of Tropical Storm Arthur in the Atlantic on May 31. Alma was also the first tropical storm in the basin to have its name retired.
Alma killed 11 people, 4 of them directly. It also caused $35,000,000 (2008 USD) in damage.
|Formation||May 29, 2008|
|Dissipation||May 30, 2008|
|Highest winds||65 mph|
|Lowest pressure||994 mbar|
|Deaths||4 direct, 7 indirect|
|Damages||$35,000,000 (2008 USD)|
|Areas affected||Central America|
|Part of the||2008 Pacific hurricane season|
Unlike most Eastern Pacific storms, Alma appears to have developed without the assistance of a tropical wave. Instead, it developed from a nearly stationary trough that was draped across the far eastern Pacific Ocean in late May. Early on May 27, a low-pressure area formed within the broad, monsoon-like flow associated with the aforementioned trough while located about 225 miles southwest of the coast of Nicaragua. The low may have been triggered by an eastward-moving area of disturbed weather. The low moved eastward, steered by the large cyclonic circulation with which it was embedded. At 0545 UTC May 28, the first Dvorak classifications were taken on the low. Subsequently, convection associated with the low continued to become better organized, and it was consequently upgraded to a tropical depression by 0000 UTC May 29 while located about 85 miles west-northwest of Cape Blanco, Costa Rica. This made the genesis point of Alma the farthest east on record for the Eastern Pacific basin (though this does not include tropical cyclones that originated in the Atlantic, crossed Central America, and subsequently reformed in the Eastern Pacific). After forming, the depression moved northward and quickly strengthened into a tropical storm. Alma continued to intensify, and microwave satellite imagery indicated an eye-like feature embedded within the center of the tropical cyclone around 1200 UTC 29 May. By 1800 UTC, Alma reached its peak intensity of 65 mph while located only 45 miles southwest of Managua, Nicaragua. Alma maintained this intensity up until its landfall near Leon, Nicaragua near 1945 UTC May 29.
After landfall, Alma began weakening, but maintained tropical storm status up until it crossed into southern Honduras around 0000 UTC May 30. Six hours later, Alma weakened to a tropical depression, and by 1800 UTC that day, Alma dissipated over the mountains of western Honduras. However, Alma's mid-to upper-level remnants entered the western Caribbean and it, combined with a passing tropical wave, triggered the development of Atlantic Tropical Storm Arthur in the western Caribbean Sea just a day later.
Upon becoming a tropical cyclone, the government of Costa Rica issued a Tropical Storm Warning for the entire Pacific side of the country. Around four hours prior to landfall, Tropical Storm Warnings were up for all of the Pacific side of Costa Rica, Nicaragua, Honduras, and El Salvador. When the National Hurricane Center indicated that the cyclone was nearing hurricane strength, they promptly issued a Hurricane Watch for the Pacific coasts of Nicaragua and Honduras, and at that point, Alma was forecast to become a hurricane. Prior to landfall, the NHC remarked that Alma could produce as much as 20 inches of rain, which would trigger devastating flash flooding and associated mudslides across the mountainous portions of Central America. The National Emergency Commission of Costa Rica activated emergency storm shelters prior to Alma's landfall. In Parrita, a total of 250 residents evacuated their homes due to the threat from Alma. In total, Nicaraguan officials evacuated around 5,000 residents throughout the country, while around 3,000 troops were deployed to assist in the aftermath of the storm.
Alma produced heavy rainfall across portions of Central America.