Published: Jun 05, 2013 11:15 AM EDT
Updated: Jun 05, 2013 5:02 PM EDT

ST. PETERSBURG, Fla. (AP) - People along Florida's west coast can expect torrential downpours, flooding and possibly a tornado because of a low-pressure system in the Gulf of Mexico starting on Wednesday.
    
Rodney Wynn, a meteorologist at the National Weather Service, said some areas will get 3 to 5 inches of rain over the next two or three days.
    
"It's going to be along the coastal regions," Wynn said. "We can't say any one county's going to get more."
    
The National Weather Service has issued flood watches Wednesday from Lee County in southwest Florida to Levy County on the northern Gulf Coast. There is a 50 percent chance that the system will develop into a tropical or subtropical cyclone by Friday, Wynn said.
    
The National Hurricane Center said an Air Force reconnaissance plane is scheduled to investigate the disturbance in the Gulf on Wednesday afternoon.
    
Meteorologists will issue an updated forecast at 2 p.m.
    
Rain will begin falling Wednesday morning. The storm is expected to move north and will move over the Big Bend area by Friday.
    
Thursday's morning commute in the Tampa-St. Petersburg area could be messy, with heavy rain and wind.
    
It's not just the west coast that will be affected; the cities of Melbourne, along Florida's east coast, and Tallahassee, in northern Florida, have also issued flood watches.
    
At least one flood-prone city - Tarpon Springs, in Pinellas County - is making sandbags available to residents.
    
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