Scott visited with emergency officials Thursday in Wakulla County, in the middle of the Big Bend. Afterward, he announced that 6,000 National Guard members were on standby if needed.
"We have a hurricane," Scott declared, adding that in Wakulla County "you can see the river — the water is already coming in. We're going to see a lot of flooding down there."
Hours before Hermine's arrival, mandatory evacuations were already in effect in localized areas. A state of emergency was declared in Taylor County, on Apalachee Bay, and evacuations were ordered in several waterside communities, NBC station WTLV of Jacksonville reported.
Several neighborhoods in Franklin County, on Apalachicola Bay farther west, were also under mandatory evacuation orders, including all of St. George and Dog islands.
Rising water overwhelmed wastewater treatment plants in Sarasota County, NBC station WFLA of Tampa reported. David Cash, manager of the county's Public Utilities Division, said the plants were inundated with double the usual daily average of 14 million gallons of wastewater.
"If we have any failures, we can expect wastewater spills in some cases, backups in homes, so we're very concerned," Cash said.
More than 4,000 sandbags were filled and distributed to residents in a few hours at just one sandbag station in Ocala, in Marion County, NBC station WESH of Orlando reported.
"We've been doing this for a couple of days now," said sheriff's Lt. Chip Wildy, director of the county's emergency management bureau. "Unfortunately, we can't wait on the wind to start blowing."
But the wind was already creating problems across Florida, with worse yet to come. The state Highway Patrol closed the Sunshine Skyway Bridge on Interstate 75 between St. Petersburg and Manatee County at 1 p.m. because of winds topping 55 mph.
The system, which started as Tropical Depression 9, also led to hurricane and tropical storm advisories for parts of Georgia and the southeast corner of Alabama.
In Georgia, Gov. Nathan Deal declared a state of emergency for 56 counties, including parts of south, central and coastal Georgia. The state Emergency Management and Homeland Security Agency warned of heavy rains, flooding, tornadoes and power failures.
After making landfall, Hermine is likely to travel up the coast, forecasters warned — perhaps as far as Boston by Monday. Updated three-day forecasts projected a line of heavy rain — as much as 10 inches — stretching from the Gulf coast of north Florida to south Georgia all the way through to Delaware's Atlantic coast by Sunday night.
"It could be a very lousy holiday weekend for a large part of the population," said Kevin Roth, a meteorologist for The Weather Channel.
Skies were still sunny Thursday afternoon on North Carolina's Wrightsville Beach — but red flags fluttered in the breeze, warning of the high risk of dangerous waters. Lifeguards said the warnings were likely to remain in place until Monday.
"Before and after, that is generally when we have the most issues," Wrightsville Beach Ocean Rescue Lt. Jon Mauney told NBC station WRAL of Raleigh. "You have beautiful weather conditions, but you have large swells, large breaking waves and extremely strong rip currents."
Gov. Pat McCrory declared a state of emergency in 33 eastern counties, and a mandatory evacuation order was in place for Ocracoke Island.
Besides downed trees and flooding, Hermine is also likely to dampen Florida's efforts against the Zika virus. Because Zika-carrying mosquitoes thrive in and around standing water, Scott told residents to empty any containers full of water as soon as it was safe to do so.
"You've heard the message with Zika. We want no standing water. Well, we're going to have standing water when this happens," he said.
Meanwhile, in Hawaii, Hurricane Madeline was downgraded to a tropical storm, and it skirted the island. Still, heavy rain hit parts of Hawaii, and strong waves pummeled shorelines as the still-powerful Pacific storm passed.
President Barack Obama, who's attending the Pacific Islands Conference of Leaders in Oahu, asked fellow Hawaiians to heed the advice of officials ahead of an expected one-two punch of Tropical Storm Madeline and Hurricane Lester.
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