Hurricane Florence is blasting toward the Carolinas, carrying sustained winds of up to 130 mph and the threat of "life-threatening storm surge and rainfall," the National Hurricane Center says.

A hurricane warning – meaning hurricane conditions are expected within 36 hours — is in effect for a long stretch of the coast, from the Santee River in South Carolina to Duck, N.C., which is part of the Outer Banks.

Hurricane conditions will likely hit on Friday, but tropical storm conditions will arrive on Thursday, according to the hurricane center.

"Preparations to protect life and property should be rushed to completion," the agency says.

The threat has sparked a rush of evacuation efforts in South Carolina and North Carolina, with more than a million people urged to get out of Florence's way. Governors of those states have already declared states of emergency, as have the governors of Virginia and Maryland.

Forecasters have adjusted Hurricane Florence's projected path, saying that after it makes landfall, it is likely to take a more southerly route than expected. Rather than pushing up toward western Virginia, the storm's center is now predicted to move across the middle of South Carolina.

For a swath of the North Carolina shore from Cape Fear to Cape Lookout, the storm surge could range from 9-13 feet, the NHC said. In Myrtle Beach, S.C., and nearby areas, the surge could hit 6-9 feet.

As of 8 a.m. ET, Florence was 530 miles southeast of Cape Fear, N.C., moving west-northwest at 17 mph, the National Hurricane Center says.

"An Air Force Reserve Hurricane Hunter aircraft that was in the hurricane until just after midnight" recorded a peak wind gust of around 150 mph, according to the hurricane center. Florence is currently heading for ocean water with surface temperatures of around 85 degrees, meaning it will likely strengthen on its way to the East Coast.

Even with some weakening that's predicted just before it makes landfall, the storm "is expected to remain a dangerous major hurricane as it approaches the coastline," the hurricane center said.

Satellite images show the storm has maintained a distinct eye and is well organized. Its maximum sustained winds are expected to top 145 mph before losing some steam near the coast. Current forecasts call for Florence to be at least a Category 3 storm when it arrives at the Carolinas.

"A motion toward the northwest is forecast to begin by this afternoon and continue through Thursday," the hurricane center says. "Florence is expected to slow down considerably by late Thursday into Friday, and move slowly through early Saturday."

The slow movement, combined with the massive amount of moisture this storm holds, will bring dangerous rains — from 20 to 30 inches in coastal North Carolina, with 40 inches possible in isolated areas, the weather service says. In South Carolina and inland parts of North Carolina, 5 to 10 inches of rain could fall, with 20 inches possible in some areas.

"This rainfall would produce catastrophic flash flooding and significant river flooding," the hurricane center says.

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