Stay Updated on Developing Stories

Florence could threaten East Coast as a major hurricane late next week

(CNN) More and more, Florence is looking like a storm that may give the US East Coast problems as a potentially major hurricane next week.

Tropical Storm Florence, currently in the Atlantic about 1,500 miles from the coast and 765 miles from Bermuda, is expected to strengthen into a hurricane on Sunday and continue gaining power for days.

And computer models increasingly are showing it could be dangerously close to the United States late Thursday. The window for the storm to miss the US coast and turn harmlessly back to sea is closing, CNN forecasters said.

"It looks like now that (computer model) consensus really kind of puts it between Georgia and North Carolina," though other states along the coast should watch as well, CNN meteorologist Allison Chinchar said Saturday afternoon.

"If you live anywhere along the East Coast, you want to be paying attention, because even if you (aren't at) the main landfall point, you're still likely to have impacts," including heavy rain and rip currents, she said.

Track the storm and compare different forecast models

A forecast cone, created midday Saturday, shows the probable range of Florence's center for five days.

Virginia and North Carolina and South Carolina already are on alert. Their governors declared states of emergency Friday and Saturday.

"While the impacts of Tropical Storm Florence to Virginia are still uncertain, forecasts increasingly expect the storm to strengthen into a major hurricane that could seriously affect the East Coast and Virginians," Virginia Gov. Ralph Northam said Saturday in a news release.

"We are preparing for the worst, and of course hoping for the best," South Carolina Gov. Henry McMaster said, adding his declaration would allow state agencies to deploy assets quickly to the coast.

North Carolina Gov. Roy Cooper waived certain transportation restrictions so that farmers could harvest and move crops more quickly.

Cooper also urged people to learn what evacuation routes to take, and put fuel in their vehicles in case they're ordered to leave.

"Action today can avoid losses due to Florence," he said.

Forecast models for Florence's possible path, as of 11:15 a.m. ET Saturday

The Navy said Saturday that it may be necessary to send ships in the Norfolk, Virginia, area out to sea because of the coming storm. The Navy put them on Sortie Condition Bravo, which means the onset of destructive weather is within 48 hours.

In a news release, the Navy said the ships can handle destructive weather better while at sea and that "having the ships underway also makes them ready and available to respond to any national tasking, including any needed disaster response efforts in the local area after the storm has passed."

Why Florence is expected to strengthen

Florence already had been the first major hurricane of the 2018 Atlantic season earlier this week, but wind shear weakened it to a tropical storm.

As of Sunday morning, Florence's center had maximum sustained winds of 70 mph.

Tropical Storm Florence appears in a satellite image from Saturday morning.

But the shear is abating and the storm is approaching warmer waters -- conditions that could allow Florence to become a hurricane again on Sunday and a major hurricane -- meaning a Category 3 storm or greater -- by Monday, the National Hurricane Center said.

Bermuda and the US East Coast are beginning to see the first impacts of Florence. Some swells generated by the storm have already been reported and can potentially cause dangerous surf conditions and rip currents.

Two other storms brewing

Behind Florence are two other storms that the National Hurricane Center is monitoring.

Tropical Depression Nine became Tropical Storm Isaac on Saturday afternoon over the eastern tropical Atlantic, the National Hurricane Center said. It was about 1,500 miles from the easternmost Caribbean islands on Sunday and may become a hurricane by Monday.

The hurricane season in the Atlantic will hit its peak Monday.

Behind Isaac is Tropical Storm Helene, which was moving across the southernmost Cabo Verde Islands off West Africa on Sunday morning and will become a hurricane late on Sunday, the National Hurricane Center said.

The three tropical systems -- Florence, Isaac and Helene -- come right before the Atlantic hurricane season hits its peak Monday. The eight weeks around that date often are prime time for the conditions that fuel powerful storms.

CNN's Haley Brink, Brandon Miller and Judson Jones contributed to this report.
Outbrain