Forecasters warned residents from Florida to Louisiana to be ready this weekend for Dennis, with top winds already at 135 mph. The hurricane turned into a Category 4 storm Thursday evening as it gained strength while barreling through the Caribbean toward the Gulf of Mexico.
At 8 a.m. EDT, Dennis' center was about 230 miles southeast of Havana, Cuba, and about 285 miles south-southeast of Key West, Florida. It was moving northwest at about 12 mph, but was expected to pick up speed and hit central Cuba later in the day.
"At this stage, it appears it will be the strongest landfall for Cuba ever in the month of July," said National Hurricane Center deputy director Ed Rappaport on CBS News' The Early Show.
Forecasters expect Dennis to hit the straits of Florida overnight, with the center passing near or just west of the lower Florida Keys, where there is now a hurricane warning in effect.
Landfall on the northeastern Gulf Coast is expected late in the weekend.
"Right now, it's category 4 intensity. We think there will be a little weakening over Cuba, but then re-strengthening is possible," Rappaport told co-anchor Russ Mitchell. "We think we'll have a major hurricane passing by the Florida Keys, probably still a major hurricane, category 3 perhaps, maybe a little bit stronger when landfall occurs on the mainland late this weekend."
Many in the hurricane's projected path already got a wake-up call this week from a surprising Tropical Storm Cindy that caused three deaths, knocked out power to thousands, and spawned twisters that toppled trees and caused up to $40 million damage to a famed NASCAR track.
"We're trying to get ready for whatever happens. We've been through so much already," Jose Davila said as he painted a house in Port Charlotte, where blue tarps still dot the rooftops of homes waiting to be repaired from Hurricane Charley, the first of a record four hurricanes to hit Florida last year.
Tourists throughout the Florida Keys were ordered to evacuate, as were all mobile home residents — and all southernmost residents of the island chain. A hurricane warning was issued for the lower Keys and Gov. Jeb Bush declared a state of emergency.
"We end up getting married at 3:30 because the hotel evacuated us," said a bride in Key West. "So we have to leave now, so this is my wedding night."
Lines of cars were seen streaming out of the island chain Thursday.
"It's a nightmare. We came here for vacations. Here we are, spending about half an hour just waiting for gas," one motorist told CBS station WFOR.
Airlines reported that nearly all flights out of Key West were full, and Greyhound added buses to help get residents out of the area.
At Cape Canaveral, the space shuttle Discovery was considered to be safe on its launching pad for now, and NASA still aimed for a liftoff next week — the first shuttle mission since the Columbia disaster.
But shuttle managers decided Thursday evening to begin initial preparations to move Discovery from the pad. A final call on whether to haul the shuttle back to its hangar was expected Friday afternoon.
People are especially nervous in places like Pensacola, Fla., still rebuilding from Ivan's destruction last September, reports.
Only about 60 percent of rental properties in Gulf Shores, Ala., have reopened since Hurricane Ivan 10 months ago, with damaged roofs and empty buildings still spotting the beachfront.
"I'm worried about flying trash cans and two-by-fours," said Nick Primozic.
In Louisiana, preparations for Dennis were delayed by the aftermath of Cindy, which caught many by surprise when it moved ashore Tuesday night with 8 inches of rain and 70-mph winds that knocked out power to about 287,000 customers, the largest blackout since Hurricane Betsy 40 years ago.
In Leeville, along Louisiana's marshy coast, fishing boats were dashed against a bridge, roofs were torn off buildings, and at least one collapsed — a scene that caused some to suggest Cindy packed the punch of a Category 1 hurricane.
Cindy's remnants dumped up to 4 inches of rain Thursday on mountainous regions of western North and South Carolina.
Two deaths were blamed on Cindy in Georgia, where the remnants dumped up to 5 inches of rain and caused damages estimated at $75 million statewide. A traffic fatality was blamed on the storm in Alabama.
In Hampton, south of Atlanta, a suspected F-2 tornado — packing winds of 113 to 157 mph — blew off roofs and popped out windows to luxury boxes at Atlanta Motor Speedway, causing damage estimated at $25 million to $40 million.
"Everything but the track surface has suffered some kind of damage," said track president Steve Clark. "We don't know to what extent yet, but it's major. There are some buildings that will have to be torn down."