North Atlantic Ocean: Tropical Depression Fred tracking west-northwestward across northern Haiti early Aug. 12 /update 4

Event

Tropical Depression Fred is tracking west-northwestward across northern Haiti early Aug. 12. As of 02:00 AST, the storm's center of circulation was approximately 27 km (17 miles) south of Cap-Haitien. Forecast models indicate the system will maintain its strength as it enters into the North Atlantic Ocean northwest of Haiti the morning of Aug. 12. Fred will track west-northwestward off the northern coast of Cuba and regain tropical storm strength by early Aug. 13. The storm is likely to continue strengthening as it turns northwestward, crossing the Florida Keys early Aug. 14 and continuing northward to make an additional landfall as a tropical storm over the Florida panhandle late Aug. 15. Fred is forecast to weaken rapidly as it tracks northwards over western Florida and southwestern Georgia through Aug. 16. Some uncertainty remains in the track and intensity forecast, and significant changes could occur in the coming days.

Authorities have reported power outages in the Dominican Republic that are affecting at least 300,000 people. Swollen rivers also caused part of the aqueduct system in the Dominican Republic to shut down, disrupting supplies to around 500,000 people.

Government Advisories
As of 02:00 AST Aug. 12, the following warnings and watches are in effect:

• Tropical Storm Watch: Haiti, from the northern border with the Dominican Republic to Gonaives; Turks and Caicos; southeastern Bahamas; the Cuban provinces of Ciego de Avila, Camguey, Las Tunas, Holguin, Granma, Santiago de Cuba, and Guantanamo.

Officials could issue new warnings and/or watches in response to the developing system in the coming hours.

Hazardous Conditions
The storm will likely bring heavy rainfall, strong winds, and rough seas to coastal areas in the Caribbean through at least Aug. 13. Sustained heavy rainfall could trigger flooding in low-lying communities near streams, creeks, rivers, and urban areas with easily overwhelmed stormwater drainage systems. Sites located downstream of large reservoirs could experience flash flooding after relatively short periods of intense rainfall. Forecast models indicate 7.5-13 cm (3-5 inches) of rainfall likely across the Dominican Republic and across western Bahamas. Models also indicate 2.5-7.5 cm (1-3 inches) of rainfall over Haiti, the Turks and Caicos Islands, eastern Bahamas, and Cuba through at least Aug. 13. Torrential precipitation could trigger flash floods and mudslides. Heavy rainfall is likely to impact parts of Florida starting Aug. 13 and through Aug. 16.

Prolonged sea swells and storm surge generated by the system may result in coastal flooding. Persistent onshore flow could make it difficult for the surge to recede and for water levels to decrease in coastal river catchments. In addition to the heavy rain, flooding, and storm surge, the storm could produce damaging wind gusts, resulting in power outages due to fallen trees and toppled utility lines.

Transport
In addition to the immediate threat to personal safety, inclement weather associated with the storm could trigger localized business, transport, and utility disruptions in areas impacted by the system. Floodwaters and debris flows may render some bridges, rail networks, or roadways impassable, impacting overland travel in and around affected areas. Areal flooding in urban locations could also result in severe traffic congestion, while strong winds will pose a hazard to high-profile vehicles. Heavy rain and low visibility may trigger flight disruptions at regional airports.

Disruptions triggered by inclement weather and resultant hazards, such as flooding, could persist well after conditions have improved. If there is severe damage to infrastructure, repair or reconstruction efforts may exacerbate residual disruptions.

Advice

Activate contingency plans in areas where officials forecast adverse conditions. Heed all evacuation orders. Use extreme caution in low-lying coastal areas and near streams, creeks, and other waterways due to the high potential for severe flooding and storm surge. Stockpile water, batteries, and other essentials in advance. Charge battery-powered devices when electricity is available; restrict the use of cellular phones to emergencies only. Power down mobile devices when not in use. Keep important documents in waterproof containers. Observe strict food and water precautions, as municipalities could issue boil water advisories following flooding events. Take precautions against insect- and waterborne diseases in the coming days. Keep any necessary medications in a waterproof container.

Plan accordingly for protracted commercial, transport, and logistics disruptions in areas in the path of the storm, especially if vital infrastructure is damaged. Seek updated information on road conditions before driving or routing shipments through areas where flooding has occurred. Confirm flights before checking out of hotels or driving to the airport; clearing passenger backlogs may take several days in some locations.

Resources

US National Hurricane Center
National Weather Service
Cuba Instituto de Meteorologia (Spanish)
Dominican Republic Oficina Nacional de Meteorologia (Spanish)
Haiti Centre national de meteorologie (French)