Michael, the third most powerful hurricane ever to hit the USA mainland, weakened overnight to a tropical storm but marched northeast on Thursday, toppling trees with 50 miles per hour (80 kph) winds and bringing "life threatening" flash flooding to Georgia and Virginia, the National Hurricane Center (NHC) reported.
The system has now graduated to Category 2 hurricane status and is expected to reach Category 3 (with winds in excess of 110 mph) when it makes its USA mainland landfall on Wednesday afternoon.
The National Weather Service is now warning that Michael is a "potentially catastrophic" weather event, which could result in "the strongest hurricane to landfall" upon Florida's Panhandle in over a decade.
At around 9 a.m. ET, Klotzbach reported that Michael had max sustained winds of 145 miles per hour, which is faster than any to reach the area since measurements began in 1851.
"Michael is likely to produce potentially catastrophic wind damage where the core of the hurricane moves onshore in the Florida Panhandle, and everyone in the hurricane warning area should prepare for life-threatening hurricane winds".
The storm is expected to bring four to seven inches of rain in north-central North Carolina and southeast Virginia, and tornadoes are still possible in these areas.
Already, flood waters have swamped hard hit areas. Only first responders were allowed in and an 8 pm curfew was imposed. Entire roofs were torn away and dropped onto a road.
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He said the auction house was still "busily figuring out" how the transaction for the now radically altered work will play out.
After hitting Florida, Michael will move north-eastward across the southeastern part of the country Wednesday night and Thursday, according to the NHC. Authorities were also searching for a boy swept away by a river in Guatemala.
"If you decide to stay in your home and a tree falls on your house or the storm surge catches you and you're now calling for help, there's no one that can respond to help you, " Mr Morgan said at a news conference.
Scott declared a state of emergency for 35 Florida counties, from the Panhandle to Tampa Bay, activated hundreds of Florida National Guard members and waived tolls to encourage evacuations.
"If you're responsible for a patient, you're responsible for the patient".
"Our biggest thing is the downed lines and the downed trees", said Apalachicola Mayor Van Johnson. Many filled sandbags and boarded up homes and lined up to buy gas and groceries before leaving town.
There will be no shelters open in Wakulla County, the sheriff's office warned on Facebook, because they are rated safe only for hurricanes with top sustained winds below 111 miles per hour (178 kph).
"This was my sixth (hurricane), so I thought I was prepared", he said. With Michael's winds projected to be even stronger, residents were urged to evacuate inland.
Tallahassee Mayor Andrew Gillum, who is also the Democratic gubernatorial candidate in the November 6 elections, said on Sunday he was cancelling his campaign events and returning to Tallahassee, the state capital, to focus on storm preparations. "There's nothing between us and this storm but warm water' and I think that's what terrifies us about the potential impacts".