About 215,000 homes and businesses in Florida are without power as Hurricane Nicole bears down on the US state.
Emergency and evacuation orders have been put in place and residents have been urged to stay indoors as heavy rain and storms are forecast.
Nicole has already hit the Bahamas as a massive Category 1 hurricane and caused widespread flooding.
Storms of this size this late in the year are extremely rare.
Nicole made landfall on Florida’s east coast as a hurricane at 03:00 EST (08:00 GMT) with sustained winds of up to 75 mph (120 km/h). These have weakened slightly to around 60 mph and Nicole has been downgraded to a tropical storm as it makes its way northwest across the Sunshine State.
The storm is expected to weaken further as it heads north toward Georgia and the Carolinas over the next two days.
Its remnants could potentially even hit Ohio, Pennsylvania and New York later in the week.
Most of Florida’s 22 million residents remained under tropical storm, high wind and storm surge warnings along with local hurricane advisories urging people to stay indoors and watch for flooding.
Forty-five of the state’s 67 counties are under a state of emergency and four counties are under a mandatory evacuation order.
The NHC has warned of flooding caused by wind-driven waves flowing inland in low-lying areas, and said strong winds are likely to bring down trees and power lines. Footage on social media showed this was already underway.
Fifteen emergency shelters have been opened, 20 school districts have closed their facilities and 1,600 utility workers are on standby to restore power.
Ahead of Nicole’s arrival, Disney World and Universal Orlando Resort closed early Wednesday and Orlando International Airport grounded commercial flights.
Nicole’s arrival is also expected to further disrupt Nasa’s long-delayed rocket launch, which aims to bring Americans one step closer to returning to the Moon.
The Artemis 1 mission had already been postponed to November 19, but there are fears that flying debris from the storm could damage the exposed rocket.
Nicole’s late arrival follows a relatively quiet storm season – for the first time since 1997, not a single hurricane or tropical storm formed in the Atlantic basin this August.
November hurricanes are rare in Florida. Since record-keeping began in 1853, the solar eclipse has been affected by only two: 1935 and 1985.
Nicole comes just weeks after Hurricane Ian hit Florida, killing more than 140 people and causing $60 billion worth of damage.