[Breaking News Update 11:30 p.m.]
The National Hurricane Center has issued hurricane and storm surge warnings for South Florida. The warning extends from Jupiter Inlet on the east coast of the state, southward around the Florida Peninsula to Bonita Beach on the west coast. The warning included the Florida Keys, Lake Okeechobee, and Florida Bay. The same area had previously been under a hurricane watch.
[Story last published 10:51 p.m. ET]
Conditions in the Turks and Caicos deteriorated Thursday as deadly and massive Hurricane Irma moved in on the islands -- and continued tracking toward South Florida where it could slam Miami this weekend.
"It has become more likely that Irma will make landfall in southern Florida as a dangerous major hurricane, and bring life-threatening storm surge and wind impacts to much of the state," the National Hurricane Center said Thursday.
The hurricane center forecast moved the most likely path of the eye of the storm to the west in its 5 p.m. ET advisory.
"It looks like it's shifting, even though it may be just 20 miles, it puts Miami right in the worst possible position," CNN meteorologist Tom Sater said.
"Because when you look at the formidable storm, the strongest winds, the strongest storm surge, the bands of heavy rain are always in that north, northeastern quadrant.
But Sater cautioned that some models show the storm farther west and some farther east. It is still more than 600 miles from Florida.
Irma, a Category 5 storm churning in the Atlantic with 175 mph sustained winds, killed at least 10 people on Wednesday as it devastated small northeastern Caribbean islands such as Barbuda and left hundreds of thousands of customers in Puerto Rico without power.
"Regardless of which (Florida) coast you live on, be prepared to evacuate," Florida Gov. Rick Scott said Thursday at a news conference, with forecasters warning the storm could reach South Florida by Sunday.
— National Hurricane Center (@NHC_Atlantic) September 7, 2017
Mandatory evacuations have been issued for many counties in South Florida, but Scott said others in Florida need to watch Irma's path and be ready to move.
"This is not a storm you can sit and wait through," he said. He added later: "You don't have to drive hundreds of miles or leave the state to be safe. Go to shelters."
Georgia, too, is ordering coastal evacuations. People in the Savannah area and everywhere along the coast east of Interstate 95 -- including Brunswick and St. Simons Island -- are ordered to leave, starting Saturday, Gov. Nathan Deal said.
Irma still was battering the mountainous, northern parts of Haiti and the Dominican Republic on Thursday afternoon. It could dump up to 15 inches of rain there -- an amount that could trigger dangerous flooding and mudslides, the US National Hurricane Center said.
Meanwhile, the northeastern Caribbean islands just hit by Irma are anxiously watching Hurricane Jose to the east. On Thursday, Antigua and Barbuda issued a hurricane watch for Jose, which could pass close to those islands Saturday. Prime Minister Gaston Browne said the government has called for voluntary evacuations from Barbuda.
Irma left at least 10 people dead Wednesday, including four on St. Martin, four in the US Virgin Islands, one on Anguilla, and one on Barbuda, officials said. The latter is barely habitable, with nearly all its buildings damaged, Browne said.
Jose became the third major hurricane of the Atlantic basin season on Thursday, with winds of 120 mph, according to the National Hurricane Center. The Category 3 storm is about 625 miles east-southeast of Antigua.
Here are the latest developments
-- Around 8 p.m. ET, Irma's center was about 55 miles west-southwest of Grand Turk Island, moving west-northwest with maximum sustained winds of 175 mph. Hurricane-force winds could be felt as far as 70 miles from the center. Irma previously had winds over 180 mph, keeping those speeds longer than any storm ever recorded in the Atlantic basin.
-- Irma could cross the southeastern Bahamas on Thursday evening and be near the central Bahamas on Friday.
-- Hurricane warnings are in effect for parts of Cuba, the Dominican Republic, Haiti, the Turks and Caicos Islands, and the southeastern, central and northwestern Bahamas.
-- A hurricane watch has been issued for Jupiter Inlet on Florida's east coast to Bonita Beach on the west coast. It includes the Florida Keys to Lake Okeechobee.
-- Gov. Scott said Thursday he has directed Florida law enforcement to escort gas trucks to gas stations in an attempt to address reported fuel shortages. "We know fuel is very important" as people prepare to evacuate inland, he said. "While we're making progress, you will see lines and outages, unfortunately."
-- Irma is one of three active hurricanes in the Atlantic basin -- the last time this happened was in 2010.
Southeastern US bracing for storm's arrival
Some computer models show Irma nearing Florida's southern and east coasts by Sunday, and potentially threatening Georgia and South Carolina later. Florida officials are ordering some evacuations and shutting down schools.
Many Floridians spent Thursday stocking up on food or making plans to head inland. Video from CNN affiliate WSVN showed Miami International Airport crowded with people waiting to leave the area.
Miami resident Ashley Hahn was at a beach Thursday with her 4-year-old daughter, saying they were taking a final few dips before fleeing the storm.
"It is chaotic with the lines and gasoline and waiting for water -- you kind of need a break," she said.
"We are probably going to head north, just to be safe. I went through (1992's Hurricane) Andrew as a child, and ... I have seen videos of destruction and everything that it entails. I don't want (my daughter) to be around for that."
Florida is not the only state preparing for possible impact.
Georgia's Gov. Deal declared a state of emergency for 30 counties. North Carolina Gov. Roy Cooper and South Carolina Gov. Henry McMaster also declared states of emergency.
Turks and Caicos, Bahamas in Irma's path
Irma was bringing heavy rain and powerful winds to the low-lying Turks and Caicos Islands on Thursday afternoon. Residents were told to stay put.
"Right now our advice would be that they shelter in place," said Virginia Cloveau, the director of the Department of Disaster Management and Emergencies. "The winds have started picking up. We are experiencing tropical-force winds so it may be too dangerous to be outdoors."
Storm surges could reach up to 20 feet, the National Hurricane Center says -- twice as high as some of the islands' elevations.
"Some of these Turks and Caicos (Islands) will be completely overwashed," CNN meteorologist Chad Myers said.
The Turks and Caicos are a British overseas territory with about 35,000 people. Officials there are "working intensively on disaster preparedness and response ... (and) liaising with their counterparts in the Cayman Islands for assistance," UK Foreign and Commonwealth Office Minister Alan Duncan said Thursday.
The Bahamas, a nation of about 390,000, ordered evacuations for six southern islands -- Mayaguana, Inagua, Crooked Island, Acklins, Long Cay and Ragged Island.
"This is the largest such evacuation in the history of the country," Prime Minister Hubert Minnis said.
Trail of destruction
Irma's eye passed directly over Barbuda on Wednesday, leaving the small island's 1,800 residents largely incommunicado for hours because it knocked over the telecommunications system and cell towers.
About 95% of the buildings in Barbuda, one of two major islands in the nation of Antigua and Barbuda, are damaged, Browne said.
"It looks like (a) garbage disposal," Marlon Carr, a photographer who toured the island with the Prime Minister of Antigua and Barbuda, told CNN on Thursday. "There was rubble and roof galvanized all over the island. It looked like some of the houses ... were imploded on."
Witnesses told him of "40-foot containers flying, animals flying" during the storm. Some spoke of taking shelter in bathrooms as their homes were torn apart.
Browne estimated the damage will cost $100 million to rebuild.
In St. Thomas in the US Virgin Islands, Kelsey Nowakowski posted images to Instagram of the aftermath there.
"This doesn't look like it was ever a tropical paradise. It looks like an eerie fairytale forest," she said in her post.
In Puerto Rico, about 56,680 customers were without water, with the island's northeast hit the hardest, according to Jesus Poupart of the emergency operations center. Emergency officials are still taking in reports to determine the extent of the damage.
In the beachside area of Piñones near San Juan, Irma tore the roof off Cristian López's fried-food restaurant. He said he wouldn't be able to reopen the place for about five days.
"At least we are all alive," he said.
In the northeast city of Fajardo, authorities conducted at least 10 rescues, an emergency dispatcher there told CNN. Of those, five were from flooded homes, two of people trapped in vehicles, and three who were trapped in an elevator, the dispatcher said.