The southern US state of Alabama has been hit full-on by Hurricane Ivan, with winds of up to 135mph (217km/h) battering the coastline.
Winds and storm surges are threatening coastal areas
Ivan, which has already killed more than 60 people in the Caribbean, pounded a 370-mile stretch of the Gulf Coast, from Louisiana to Florida.
There was relief in New Orleans, spared a direct hit, but Ivan was blamed for 12 deaths in Florida and Louisiana.
Further south, Tropical Storm Jeanne is now a hurricane - the season's sixth.
Two deaths were reported in Puerto Rico as Jeanne crashed ashore before heading towards the Dominican Republic and the Bahamas.
And as the Caribbean continues to reel from the effects of Hurricane Ivan, the Red Cross has launched a $4.8m appeal to help tens of thousands of people made homeless.
State of emergency
Hurricane Ivan made landfall near the port of Mobile, Alabama, at about 0300 (0700 GMT), bringing ferocious, swirling winds and heavy rains.
"We have never seen a hurricane of this size come into Alabama," said Governor Bob Riley.
Most people had heeded the governor's advice and moved inland, while those remaining behind were crammed into emergency shelters.
It was the worst weather to hit the area in 25 years and left 100,000 people without power.
The BBC's Matt Frei in Mobile says the destruction was not as bad as predicted, although he described seeing streets littered with felled trees, traffic lights ripped from their power lines and torn billboards.
Change of course
At 1500 GMT on Thursday, the US National Hurricane Center said Ivan was weakening as it continued to move northwards across Alabama at 14mph (24km/h).
However, it added that tornadoes were possible over the next 24 hours in eastern Alabama, the Florida panhandle, western Georgia, eastern Tennessee, western South Carolina and western North Carolina.
This image taken at 0100 GMT on Thursday shows Ivan on the left and then Tropical Storm Jeanne
New Orleans was spared early on Thursday after Ivan changed course, leaving the city with little visible damage.
On Wednesday, the main route out of New Orleans had been clogged with traffic as residents fled the area, but the much-feared devastation failed to materialise.
About 30,000 people in the city suffered a power cut after falling trees brought down power lines, but otherwise the storm brought little more than overnight gusts of wind and some light rain.
Waves - some up to 25ft (7.5m) - destroyed homes along the Florida shoreline, the Associated Press reported.
Officials in north-west Florida said at least eight people had died in tornadoes produced by the storm.
Four sick evacuees, including a terminally ill cancer patient, died after being taken from their storm-threatened homes in southern Louisiana to safer parts of the state, AP reports.
The US National Hurricane Center has warned people not to venture out during the calm conditions of the eye.
"Winds will increase rapidly with little or no warning when the eye passes," it said.
Flood waters in Grand Cayman are slowly receding
Meanwhile, relief efforts in areas already hit by Ivan are continuing, with the International Federation of Red Cross and Red Crescent Societies launching a $4.8m appeal to help Caribbean victims.
The Red Cross aims to support 85,000 people over the next six months in Grenada, Jamaica, the Cayman Islands and Cuba.
Operations co-ordinator Ian Logan told BBC News Online that conditions were especially bad in Granada, where 90% of buildings have been damaged.
"We're looking at 60,000 people in Grenada who've lost everything, and that's out of a population of 100,000," he said.
He added: "We've already had three hurricanes in a row that were category four or five in strength. This could be a one-in-50-year season. It's a devastating picture so far and we have to assume that there will be more."
In Jamaica, where 15,000 people are staying in public shelters, officials say more than 30 fishermen are missing after the island was hit last Friday.
There was a mass evacuation of western areas of Cuba, but the island escaped with minimal damage after the centre of the storm barely touched land.
An overnight curfew remained in effect in the Cayman Islands, where the hurricane wrought havoc on Sunday.
PREDICTED PATH OF HURRICANE IVAN