North Atlantic Ocean: Tropical Depression Five forms in the southern North Atlantic Ocean late June 30

Event

Tropical Depression (TD) Five has formed in the southern North Atlantic Ocean late June 30. As of 23:00 AST, the storm's center of circulation was approximately 1,505 km (935 miles) east-southeast of Bridgetown, Barbados. Forecast models indicate the system will track westward and strengthen into a tropical storm by early July 1. TD Five will likely make a close approach to Barbados early July 2 and pass between Saint Lucia and Saint Vincent and the Grenadines to enter the Caribbean Sea later the same day. The storm is forecast to maintain its strength and course, possibly making an initial landfall over southwestern Haiti late July 3, followed by southwestern Cuba early July 4. TD Five will maintain its intensity and turn to track in a northwesterly direction over Cuba and the Straits of Florida through late July 5. Some uncertainty remains in the track and intensity forecast, and significant changes could occur in the coming days.

Government Advisories
As of 23:00 AST June 30, the US National Hurricane Center has issued the following warnings and watches:

• Tropical Storm Warning: Barbados, Martinique, and Saint Lucia

• Tropical Storm Watch: Guadeloupe and Saint Vincent and the Grenadines

The Barbados Meteorological Services has issued flash floods, small craft, and high surf advisories warning of increasing swells of 2-3 meters (7-10 feet) and rainfall accumulations of 5-10 cm (2-4 inches). The Dominica Meteorological Service has also issued a flash flood warning nationwide with a rainfall forecast of 5-7.5 cm (2-3 inches).

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

Hazardous Conditions
TD Five will likely bring heavy rainfall, strong winds, and rough seas to coastal areas in the Windward and southern Leeward Islands through at least July 2. 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 7.5-15 cm (3-6 inches) of rainfall are likely over portions of the Windward and southern Leeward Islands, including Barbados. Higher totals of 20 cm (8 inches) are possible in areas affected by persistent bands of thunderstorms. Flooding could trigger flash floods and mudslides, isolating some communities for several days.

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, TD Five 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 through at least July 2 in coastal areas of the Windward and southern Leeward Islands, including Barbados. 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
Barbados Meteorological Services
Cuba Instituto de Meteorologia (Spanish)
Dominican Republic Oficina Nacional de Meteorologia (Spanish)
Dominica Meteorological Service
Grenada Meteorological Office
Haiti Centre national de meteorologie (French)
Jamaica Meteorological Service
Meteo-France (French)
Saint Lucia Meteorological Services
Saint Vincent and the Grenadines