Tropical Storm Alpha (2005)

Dominican Republic	9
Haïti	17
Bahamas	1
Totals	27
	Because of differing sources, totals may not match.

**Tropical Storm Alpha**
Tropical storm (SSHS)
	; Tropical Storm Alpha making landfall near Barahona in the Dominican Republic
Formed	October 22, 2005
Dissipated	October 24, 2005
	50 mph (85 km/h) (1-minute sustained)
Lowest pressure	998 mbar (hPa; 29.48 inHg)
Fatalities	26 direct, 17 indirect
Damage	Unknown
Areas; affected	Haiti, Dominican Republic
	Part of the; 2005 Atlantic hurricane season

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This article is about the 2005 tropical storm. For other storms named Alpha, see Tropical Storm Alpha (disambiguation).

Tropical Storm Alpha was the 23rd named storm of the 2005 Atlantic hurricane season. It made landfall on Hispaniola on October 21, causing heavy rain and mudslides. On October 20, tropical depression 25 formed from a tropical wave near the Windward Islands. It became a tropical storm on October 23, and reached its peak intensity. It then moved north, and made landfall in Haiti. It weakened to a tropical depression, and persisted until October 24, when it dissipated, and was absorbed within Hurricane Wilma's large circulation. It caused 43 deaths in total, 26 of them were directly related to Alpha. Heavy rain, mudslides, and moderate wind gusts caused 17 deaths in Haiti, and 9 in the Dominican Republic. 400 houses were completely destroyed in Haiti.

[edit] Storm history

Storm path

Alpha's origins were from a tropical wave that developed near the Windward Islands on October 20.^[1] Satellite images indicated that a low pressure center associated with the tropical wave formed near Barbados and moved west-northwest with increasing convective activity. In an area of light wind shear, the convection increased and doppler weather radar data from Puerto Rico detected a well-defined cyclonic circulation.^[1] On October 22, the area of low pressure organized into Tropical Depression 25, southeast of Hispaniola.^[2] Shortly thereafter, satellite imagery indicated that a closed circulation had developed, and the associated convection had started banding.^[3] Later that same day, the depression had organized enough to be upgraded to Tropical Storm Alpha; this was the first time the National Hurricane Center had to use a Greek name for an Atlantic hurricane.^[4]

When Alpha came within the Doppler weather radar range of Puerto Rico, the radar suggested that an eyewall-like feature had developed.^[5] Alpha was tracking along the southwest edge of a subtropical ridge.^[5] With nearby Hurricane Wilma's large circulation, Alpha was experiencing strong southerly flow from Wilma.^[5] Alpha, with its small circulation, was then faced with the mountainous terrain of Hispaniola, which led forecasters to believe Alpha was soon to dissipate.^[6] Shortly after Alpha reached its peak intensity on October 23 its wind decreased. While convection remained in bands, the low level circulation was disrupted by land, thus, leaving a very ill-defined center, which made locating the center difficult.^[7]

Late on October 23, Alpha made landfall in Hispaniola, quickly decreasing in intensity as it did so.^[8] After making landfall, the storm had weakened, leaving it just between tropical storm and tropical depression status.^[8] Because of the weakening, and the strong southerly flow from nearby Hurricane Wilma, it was hard to determine weather a low-level circulation was present.^[8] However, satellite imagery suggested that a new center had developed over open waters to the north of Hispaniola.^[8] It was downgraded to a tropical depression early the next day, now re-emerging over open waters.^[9]

The storm soon developed an elongated center of circulation which indicated that the system was weakening.^[10] On October 24, a low-level center was not present any longer, and only a small area of convective activity persisted, thus, the system dissipated, and was a remnant low pressure system when the National Hurricane Center issued their last advisories of Alpha.^[11] Shortly after, the remnant low was absorbed into the circulation of Hurricane Wilma on October 25.^[1]

[edit] Impact

In Haiti, 17 people died.^[1]^[12] Two people drowned when a river overflowed in Grande Anse. Two more people died after being electrocuted during flooding, one in the Port-au-Prince suburb of Carrefour and the other in the southern town of Jacmel.^[13] The rest of the deaths were a result of flooding in various areas in the country.^[13] In addition, 400 houses were destroyed. The largest report of rainfall was 7.9 inches at the town of Las Americas.^[1] Across the country, 243 houses were destroyed, and 191 more were damaged.^[14]

In the Dominican Republic, authorities ordered the evacuation of at least 30,000 people living in areas where flooding was possible. Nine deaths occurred there^[12], including two fishermen who went missing at sea during the storm and a fourteen year old boy who was swept away by floodwaters in the town of Guaricanos.^[12]

One indirect death occurred in the Bahamas when a boy was pulled out to sea by strong rip currents generated by Alpha.^[12]

[edit] Naming and records

Since all the twenty one predetermined hurricane names were exhausted after Hurricane Wilma, the Greek alphabet was used and the storm was designated Alpha once it reached tropical storm status. The name Alpha has been used before in the Atlantic for a subtropical storm, but 2005 was the first season to have a tropical storm Alpha.^[15]

At the time it was thought that Alpha was the twenty-second storm of the season, and so was the storm which broke the 1933 season's record for most storms in a single season. However post-season analysis revealed that there was also an earlier subtropical storm, which made Alpha the twenty-third storm of the season. Alpha was the first tropical storm to be assigned a Greek-alphabet name after the list of hurricane names was exhausted.