Florence is likely to surge back to hurricane strength and take aim for the US East Coast states of North or South Carolina, forecasters warned Saturday.
The Miami-based National Hurricane Center said its hurricane hunter aircraft -- which flies near and sometimes into storms to assess them -- found Florence "a little stronger and expected to become a hurricane again" later Saturday or early Sunday.
The storm is forecast to strike as a major hurricane on Thursday -- such a large strike has not hit that area in decades.
North Carolina Governor Roy Cooper issued an emergency on Friday to get emergency operations rolling. South Carolina followed suit on Saturday.
"Interests along the US East Coast, particularly Florida through North Carolina, should closely monitor the progress of Florence, ensure they have their hurricane plan in place and follow any advice given by local officials," the NHC said.
Large ocean swells affecting Bermuda and these US coastal areas, will continue into next week, the NHC warned, noting the "swells will result in life-threatening surf and rip currents."