Port-au-Prince: Hurricane Matthew had killed almost 900 people and left tens of thousands homeless in Haiti earlier before it skirted Florida's Atlantic coast and plowed northward over waters just off Georgia.
The number of deaths in Haiti, the poorest country in the Americas, surged to at least 877 on Friday as information trickled in from remote areas previously cut off by the storm, according to a Reuters tally of death tolls given by officials.
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Hurricane Matthew: Florida residents trapped in homes
Widespread flooding from Hurricane Matthew has trapped people inside their homes and businesses in St. Augustine, Florida. A reporter with Action News Jax shared video of people hunkering down at the Casablanca Inn on Friday.
Matthew triggered mass evacuations along the US coast from Florida through Georgia and into South Carolina and North Carolina.
It sideswiped Florida's coast with winds of up to 195km/h but did not make landfall in the state. The US National Hurricane Center (NHC) downgraded the storm to a Category 2 on the five-step Saffir-Simpson scale as its sustained winds dropped to 177 km/h. Category 5 is the strongest.
There were at least four storm-related deaths in Florida but no immediate reports of significant damage in cities and towns where the storm swamped streets, toppled trees and knocked out power to more than 1 million people.
US President Barack Obama urged people not to be complacent and to heed safety instructions.
"The potential for storm surge, loss of life and severe property damage exists," Mr Obama told reporters after a briefing with emergency management officials about the fiercest cyclone to affect the US since Superstorm Sandy four years ago.
In Daytona Beach, the street under the city's famed "World's Most Famous Beach" sign was clogged with debris washed up by the ocean. The waves had receded by early afternoon but there was damage throughout the city, including a facade ripped off the front of a seaside hotel.
Robert Walker, a 51-year-old mechanic, weathered the worst of the storm in his seaside Daytona Beach apartment where high-powered winds peeled back the roof.
"It sounded like a jet plane coming over. I was scared," Mr Walker said.
Matthew smashed through Haiti's western peninsula on Tuesday with 1233km/h winds and torrential rain. Some 61,500 people were in shelters, officials said, after the storm pushed the sea into fragile coastal villages, some of which were only now being contacted.
While highlighting the misery of underdevelopment in Haiti, which is still recovering from a devastating 2010 earthquake, the storm looked certain to rekindle the debate about global warming and the long-term threat posed by rising sea levels to low-lying cities and towns.
At least three towns in the hills and coast of Haiti's fertile western tip reported dozens of people killed, including the farming village of Chantal where the mayor said 86 people died, mostly when trees crushed houses. He said 20 others were missing.
"A tree fell on the house and flattened it. The entire house fell on us. I couldn't get out," said driver Jean-Pierre Jean-Donald, 27, who had been married for only a year.
"People came to lift the rubble, and then we saw my wife who had died in the same spot," Jean-Donald said, his young daughter by his side, crying "Mommy."
With mobile phone networks down and roads flooded, aid has been slow to reach hard-hit areas in Haiti. Food is scarce and at least seven people died of cholera, likely because of flood water mixing with sewage.
Reuters