The governors of Virginia, North Carolina and SC have declared states of emergency, warning residents to prepare for a unsafe storm. The hurricane is most likely going to be at least a Category 3 storm before making landfall in the Mid-Atlantic region of the U.S.
As of Sunday afternoon, hurricane-force winds extended outward up to 25 miles from Florence's center, while tropical storm winds extended up to 125 miles. Florence will likely become a major hurricane Monday night, and will remain a strong, risky hurricane through next week as it approaches the east coast.
Florence should be a major Category 3 hurricane later Monday morning, and a Category 4 storm, with winds of 140 miles per hour, by Tuesday.
Helene, which formed Friday night, is expected to bring tropical storm conditions to the Cabo Verde islands, off the coast of Africa, on Sunday.
USA residents from SC to Virginia were warned that Florence posed an increasing risk of life-threatening coastal storm surge, as well as flooding from heavy rainfall inland.
The peak of hurricane season is Monday, and right on cue, there are four tropical systems that are being monitored this week.
The Trinidad and Tobago Meteorological Service said it is monitoring the progress of Tropical Storms Helene and Isaac in the Eastern Atlantic.
At 11:00 AM Sunday, the center of Hurricane Florence was located by a NOAA Hurricane Hunter aircraft near latitude 24.4 North, longitude 56.3 West. The storm is expected to move west, toward the Lesser Antilles, likely impacting those islands by later this week.
The hurricane center said it was still too early to predict its exact path.
There have been six tropical storms in the Atlantic basin this year. "Florence could become a major hurricane by Monday", the NHC said.
Forecasters say that storm was about 1230 miles (1985 kilometers) east of the Windward Islands with maximum sustained winds of 75 mph (120 kmh).
Hurricane Helene has strengthened a bit and now has maximum sustained winds near 85 miles per hour.
On Saturday, South Carolina Governor Henry McMaster declared a state of emergency in anticipation of the storm.
The news release notes that plans could change if forecasts indicate a decrease in the strength or change in the track of the storm.