North Atlantic Ocean: Tropical Depression Fred tracking westward late Aug. 13; close approach to Florida Keys, Fla., forecast Aug. 14 /update 7

Event

Tropical Depression Fred continues to track westward over Cuba late Aug. 13. As of 17:00 EDT Aug. 13, the storm's center of circulation was approximately 25 km (15 miles) south-southwest of Caibarien, Cuba, and 340 km (210 miles) southeast of Key West, Florida, US. Forecast models indicate the system is likely to strengthen into a tropical storm as it moves northwestward off of coastal Cuba and into the Straits of Florida Aug. 14. The system is forecast to make a close approach to the Florida Keys, likely passing to the west of the archipelago, Aug. 14 before turning further northward and intensifying in the Gulf of Mexico Aug. 15 through early afternoon Aug. 16. The tropical storm is then forecast to make another landfall in the Florida Panhandle near Destin, Fla., afternoon Aug. 16. The system is subsequently forecast to weaken rapidly as it tracks northward over western Florida and Alabama through Aug. 17, and will likely dissipate over Tennessee or Kentucky by Aug. 18. Some uncertainty remains in the track and intensity forecast, and significant changes could occur in the coming days.

Government Advisories
As of 17:00 EDT Aug. 13, the following warnings and watches are in effect:

• Tropical Storm Warning: Florida Keys, west of Ocean Reef to the Dry Tortugas; Florida Bay

• Tropical Storm Watch: The southwest coast of Florida, from Englewood south and east to Ocean Reef

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 Cuba, the Bahamas, and Florida through at least Aug. 16. 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 the system will likely bring rainfall totaling 2.5-10 cm (1-4 inches) to parts of Cuba and 2.5-8 cm (1-3 inches) to parts of the Bahamas; through Aug. 16, 8-15 cm (3-6 inches) of rainfall is likely across the Florida Keys into central and southern Florida toward the Big Bend region of the state. Isolated greater rainfall totals are possible in Cuba, the Bahamas, and Florida. Torrential precipitation could trigger flash floods and mudslides.

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 weather 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 and necessary medications 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.

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)