PORT ST JOE, Florida (REUTERS) - Rescue crews confronted with shattered roads, fallen trees and miles of ruins struggled on Friday (Oct 12) to get to Florida Panhandle communities hardest hit by Hurricane Michael, saying they expected the death toll of 14 to rise.

None of the confirmed 14 fatalities were reported from the oceanfront communities, such as Mexico Beach, Port St Joe and Panama City, that bore the brunt of the storm's wrath, and rescuers have so far been unable to conduct thorough searches there.

"I think you're going to see it climb," Brock Long, administrator of the Federal Emergency Management Agency (Fema), said of the death count.

"We still haven't gotten into some of the hardest-hit areas."

Fema crews have been using bulldozers and other heavy equipment to push a path through debris to allow rescuers to probe the rubble with sniffer dogs as drone aircraft and Blackhawk helicopters searched from above.

Michael blew ashore near the small Florida Panhandle town of Mexico Beach on Wednesday afternoon as one of the most powerful storms in US history, with winds of up to 250kmh. It pushed a wall of seawater inland, causing widespread flooding.

The storm, which in less than two days grew from a tropical storm to a Category 4 hurricane on the five-step Saffir-Simpson scale, tore apart entire neighborhoods in the Panhandle, reducing homes to naked concrete foundations or piles of wood and siding.

Phone service to the most damaged areas was down, leaving survivors no way to contact worried relatives.

Bay County officials said 56 people chose to stay in their homes in Mexico Beach. Search and rescue teams were still trying to account for those people.

"We are still in the heat of search and rescue and do not have any information at this time," said Catie Feeney of the Bay County Emergency Services agency.

Social media websites were full of messages from people trying to reach missing family members in Florida's Bay and Gulf Counties.

Locals offered to go to addresses to see if houses had survived or if residents were there. The National Oceanic and Atmospheric Administration (NOAA) provided a website with satellite images for people to check on the condition of homes.

'WALL OF WATER'

In the coastal community of Panacea, 96km east of where Michael made landfall, Jasmine McMillan, 42, contemplated the damage at the commercial campground her family owns on Ochlockonee Bay.

"We lost our dock. It's washed away," she said. "All these electrical poles and water lines are busted."

The campground had been full just before Michael blew in and covered it in 61cm of debris and seaweed, McMillan said.

Florida Senator Bill Nelson went to Panama City, up the coast from Mexico Beach, and was stunned by what he saw.

"Pine forests were no longer - they were all sticks that were broken in two," Nelson, a Democrat, told Fox News. "Mexico Beach, there's no barrier island out there to protect it, so it got the full force of the Category 4 wind and that wall of water."

Although weaker as it pushed over the southeastern United States, the storm carried high winds and delivered drenching rains to Georgia, the Carolinas and Virginia. It killed at least four people in Florida, five in Virginia, three in North Carolina and two in Georgia, officials said.

About 1.5 million homes and businesses were without power from Florida to Virginia on Friday, according to utility companies.

It could be weeks before power is restored to the most damaged parts of Florida.

Fema's Long urged communities such as Mexico Beach, where many homes were obliterated by 3.7m to 4.3m of storm surge, to rebuild to withstand future storms.

"It's OK if you want to live on the coast or on top of a mountain that sees wildfires or whatever, but you have to build to a higher standard," he said. "If we're going to rebuild, do it right."

By Friday morning, the remnants of Michael had moved into the Atlantic Ocean north-east of Norfolk, Virginia, but still could bring up to 13cm of rain to parts of New England, the National Hurricane Centre said.

The number of people in emergency shelters was expected to swell to 20,000 across five states by Friday, said Brad Kieserman of the American Red Cross. The Coast Guard reported rescuing 129 people.

US Gulf of Mexico producers have cut oil output by 32 per cent and natural gas output by 13 per cent due to lingering effects of Michael, the Bureau of Safety and Environmental Enforcement said on Friday, citing reports from 27 companies.