Miami-Dade County

Tropical depression forms, may threaten Florida

Forecast as of 2 p.m. August 23.
Forecast as of 2 p.m. August 23.

A storm lumbering northwestward through the Caribbean packing heavy rain grew into a tropical depression Saturday night and may pose a threat to Florida.

The National Hurricane Center issued a tropical storm warning for the Turks and Caicos, and parts of the Bahamas. Moving at about 11 mph, the storm is expected to continue heading to the northwest before turning to the northeast and slowing late Sunday or early Monday to pick up steam over warm Bahamian waters, forecasters said. The center of the storm will likely pass over or near the central Bahamas Sunday or Monday.

The 11 p.m. advisory Saturday said sustained winds are near 35 mph and would become a tropical storm by Sunday.

Because the storm has remained sloppy, predicting its track has been tricky. Earlier tracking models generally agreed that the storm would make a sharp turn north and dodge the U.S. coast. The models then shifted and plotted a more gradual curve or none at all, raising the possibility that Florida could be affected.

Forecasters also expected the mountains in Hispaniola, the island shared by Haiti and the Dominican Republic, to keep the storm disorganized as it marched west. But the island’s five mountain ranges left the storm’s middle and upper levels unaffected.

As the storm cruises over warm waters northwest of the island, it will likely steadily increase in strength. Forecasters warned it could dump four to eight inches of rain over the southeastern Bahamas. Hispaniola, already saturated from seasonal spring and summer rains, could get up to a foot, forecasters said.

With its denuded mountains, Haiti is particularly susceptible to deadly mudslides and flooding triggered by rain. In 2012, relentless rain from Isaac and Sandy killed nearly 100 people and caused widespread damage to homes and crops when the hurricanes sideswiped the impoverished country.

If the storm turns north and dodges the U.S., it may still churn up dangerous coastal rip currents, said hurricane center spokesman Dennis Feltgen.

“As to how much and how long remains to be seen,” he said.

Earlier this month, National Oceanic and Atmospheric Administration forecasters updated their seasonal outlook, predicting the season would fall well below average numbers.

They predicted just five to 10 storms over the rest of the season, which runs through November. Counting Arthur and Bertha — two hurricanes that formed early in July and August — only one to four more hurricanes are forecast. The prediction for the number of major storms with winds topping 110 mph stands at up to two.

If the system strengthens to a tropical storm, it would be named Cristobal, the third named storm of the season.

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