Forecasters issued a hurricane warning for parts of Florida's Gulf Coast on Monday as the first named storm of the 2006 Atlantic hurricane season quickly gained strength in the Gulf of Mexico.
The warning from Longboat Key near Sarasota to the Ochlockonee River south of Tallahassee means Tropical Storm Alberto was expected to produce hurricane conditions within the next 24 hours.
A tropical storm warning remains in effect for Longboat Key to Englewood.
"We're talking about powerful forces of nature," Florida Gov. Jeb Bush said. "People need to take this very seriously."
At 11 a.m., Alberto's winds had increased to 70 mph, up from 50 mph just three hours earlier. The storm was centered about 190 miles south-southwest of Apalachicola and was moving north-northeast at about 7 mph, National Hurricane Center forecasters said.
The storm's sustained winds would have to hit 74 mph to make it a hurricane.
Alberto's core wasn't expected to reach Florida until Tuesday, but with tropical storm-force wind stretching 230 miles from the center, powerful gusts may be felt long before it makes landfall.
The storm's outer bands brought rain on the state Sunday, and forecasters warned that tornadoes were possible in west-central and northwestern Florida Monday night.
Heavy rain from Alberto drenched Havana, Cuba, and Pinar del Rio province to the west throughout the weekend, causing some minor street flooding. The official Prensa Latina news agency reported Monday a handful of old buildings around Havana crumbled in the heavy rains, a common occurrence during even the weakest storms, but there were no immediate reports of other major damage or injuries.
In Florida, 4 to 10 inches of rain could fall on the peninsula through Tuesday, forecasters said.
The prospect of a rain -- as long as it didn't come with hurricane-force wind -- was welcomed by firefighters who have been battling wildfires for six weeks on Florida's Atlantic coast.
"A good soaking rain would do a lot to help stop the fires in our area," said Pat Kuehn, a spokeswoman for Volusia County Fire Services. "It has been a hard fire season. We've had several fires a week here."
The tropical depression that produced Alberto formed Saturday, nine days after the official start of the hurricane season, in the northwest Caribbean, which can produce typically weak storms that follow a similar track this time of year, forecasters said. It became a named storm when its sustained winds reached 39 mph.
Scientists say the 2006 season could produce as many as 16 named storms, six of them major hurricanes.
Last year's hurricane season was the most destructive on record. Hurricane Katrina devastated Louisiana and Mississippi and was blamed for more than 1,570 deaths among Louisiana residents alone.
It also was the busiest in 154 years of storm tracking, with a records 28 named storms and a record 15 hurricanes. Meteorologists used up their list of 21 proper names -- beginning with Arlene and ending with Wilma -- and had to use the Greek alphabet to name storms for the first time.
The first named storm of 2005 was Tropical Storm Arlene, which formed June 9 and made landfall just west of Pensacola in the Florida Panhandle.