An area of low pressure likely to develop off the east coast of Florida could bring heavy rain and possible flooding to South Florida over the next couple of days and suck moisture away from the Tampa Bay area.
The National Hurricane Center is watching two areas of disturbed weather — one off the southeastern coast of Florida and another in the Caribbean Sea, the agency said in a Wednesday afternoon update. Neither currently poses a threat to the Tampa Bay area.
Off the southeast coast of Florida, forecasters expect a low pressure system to develop by Thursday. The hurricane center said the area is not likely to become tropical. The system will move northeast near the Bahamas and offshore of the east coast of the United States through the weekend, the hurricane center said.
The area of low pressure could generate gusty winds and heavy rains across portions of South Florida, the Keys and the Bahamas over the next few days, forecasters said.
The National Weather Service warned of a moderate chance of “excessive rainfall” in areas such as Fort Lauderdale and Miami on Wednesday — when urban areas could see up to 3 inches of rain in an hour and flash flooding. The weather service said there is the potential for more than 10 inches of rain through Thursday morning in the area.
Despite possible heavy downpours in South Florida, the Tampa Bay area isn’t expected to see much impact from the system.
“The only real effect it will have on our weather is, as the low develops, it’ll pull drier air in, so it’ll just diminish rain chances around here,” said Josh Linker, a meteorologist for Spectrum Bay News 9.
Linker said the system complicates Tampa Bay’s rain forecast. A separate low-pressure system in the Gulf of Mexico, which is not currently being monitored by the hurricane center, is pushing moisture into the area. The area of low pressure brought Tampa Bay’s first rainfall in nearly a month on Tuesday.
Linker said that, depending on how soon the southeastern Florida area of low pressure develops, that system could pull moisture away from Tampa Bay and diminish the area’s rain chances.
“No scenario gives us the potential for heavy rain, like widespread heavy rain,” Linker said. “In a way, if that low off south Florida develops too soon, and cuts off the moisture feed from the first one (the gulf system), then we’ll get less of the well-needed rain.”
Linker said there’s still a good shot of Tampa Bay getting widespread rain Wednesday night. However, the blob of rain off Florida’s west coast was not making much progress Wednesday morning, Linker said.
“I’m not overly optimistic that we’re going to get good rain,” Linker said.
The National Weather Service is anticipating Wednesday night will be breezy, with a 70% chance of rain across Tampa Bay. Wind speeds could reach up to 25 mph, according to a forecast for Tampa. By Thursday, there is up to a 50% chance of rain across the area.
The South Florida system is also likely to produce wind shear that will inhibit the development of another area of disturbed weather in the southwestern Caribbean Sea, Linker said. Early this week, that Caribbean system showed signs that it could develop further, but its chances of development have continued to fall.
Forecasters for the hurricane center said the system being watched in the Caribbean could still become a tropical depression this weekend, and that Caribbean islands should monitor the disturbance.
The hurricane center is monitoring these two systems just a few weeks before the official end of the hurricane season on Nov. 30. However, Linker said that the hurricane season in Tampa Bay has essentially wrapped up.
“We’re done with hurricane season and tropical weather here in Central Florida, and the Tampa Bay area,” Linker said. “That’s simply because we were done a month ago when we had that first good cold front come through.”
That cold front in early October cooled gulf temperatures and dried out the atmosphere, Linker said, making it nearly impossible for tropical air to make a resurgence this late in the season.
By Friday, rain chances in the Tampa Bay area drop to around 20%. This weekend, drier, cooler air will settle into the area, when highs top out in the upper 70s and lows could reach into the 50s in some areas.
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