Calling the flooding "catastrophic," Gov. Charlie Crist requested an emergency disaster declaration from the federal government to defray rising debris and response costs. The White House said the Federal Emergency Management Agency was reviewing the request.
Flooding was reported in hundreds of homes in Brevard and St. Lucie counties, some by up to 5 feet of standing water. In three towns, rising waters backed up sewage systems. It wasn't immediately clear how many residents had been displaced or were stranded, but county officials reported making dozens of rescues.
"We can't even get out of our house," said Billie Dayton of Port St. Lucie, as waters lapped at her porch. "We're just hoping that it doesn't rain anymore."
The storm could dump 30 inches of rain in some areas of Florida, and the National Hurricane Center said up to 22 inches had already fallen near Melbourne, just south of Cape Canaveral on the state's central Atlantic coast.
Forecasters originally expected Fay to energize over the ocean and possibly become a hurricane before landing in Florida for the third time later this week. The erratic storm first struck Monday in the Florida Keys, then veered out to sea before traversing east across the state, briefly strengthening, then stalling. For much of Wednesday, the storm barely moved, dumping inches and inches of rain over coastal central Florida.
If Fay crosses into the Atlantic and strikes Florida again, as expected, it would be just the fourth storm in recorded history to hit the peninsula with tropical storm intensity three separate times. The most recent was Hurricane Donna in 1960, said Daniel Brown, a hurricane specialist at the National Hurricane Center.
The rain was welcome in dry Florida and Georgia cropland, but could also hurt farmers' production. Forecasters predicted parts of northern Florida could get 10 to 15 inches of rain, while southern Georgia could receive 3 to 6 inches.
"They're probably areas of the state that found the rains very beneficial," said Terence McElroy, the spokesman for the Florida Department of Agriculture and Consumer Services.
But Mr. McElroy said the rain could pool around and damage citrus trees and flood pastures and hay fields.
In Florida communities to the north and in southeast Georgia, preparations included canceling school, clearing storm drains and encouraging mobile home residents to find sturdier shelter.