At 7 a.m., the center of the eye was located about 5 miles (10 kilometers) east of Wilmington, moving west at 6 mph.
Gradual weakening is forecast during the next 48 hours, but Olivia is expected to remain a tropical storm as it moves over the main Hawaiian Islands. Isaac is forecast to gradually weaken over the next few days, and could degenerate into a tropical wave during that time.
A smaller hurricane dubbed Isaac is reportedly heading for the Caribbean, while Hurricane Helene - now also in the Atlantic - is forecast to track towards the UK.
"Currently Helene is 2000km southwest of the Azores and remains a category 1 hurricane, with sustained winds of 130kph and gusts in excess of 170 kph".
Top winds were holding at 90 miles per hour - that's just a Category 1 hurricane - but some communities were already submerged in more than six feet of water as the storm drenched the coast.
Moderate to strong northwesterly shear and dry mid-level air are likely to cause Isaac to weaken to a tropical depression or even become an open wave within the next day or so, the NHC reported. This rainfall may cause unsafe flash flooding, N.H.C. said.
With Hurricane Florence, numerous coastline will see water levels from the storm surge rise over 3 feet, with some families seeing over 9 feet of water near their homes.
While Hurricane Florence has sparked state of emergency and mass evacuation, a very unfortunate weather graphic has managed to put a smile on those preparing for the storm. Expect rain chances to be more typical at 40 percent Monday, Tuesday and Wednesday.
Philippine authorities began evacuating thousands of people Thursday from the path of the typhoon, closing schools, readying bulldozers for landslides and placing rescuers and troops on full alert in the country's north.
Hurricane Helene is likely to head towards the United Kingdom, meteorologists are predicting.
Met Eireann has said that it will continue to monitor the situation surrounding the landing of ex-tropical Storm Helene, which is expected to hit Ireland early next week.
A remarkable satellite image shows Hurricane Florence in the Atlantic is one of just nine potentially unsafe storms now circling around the world.