Residents of the northern Bahamas, some trapped on the roofs of homes, have sent out pleas for help after Hurricane Dorian stalled over the area.
Dorian fell in strength on Tuesday to category three, but Grand Bahama island faced at least another day of heavy rain, high winds and storm surges.
The storm killed at least five people when it hit the Abaco Islands at category five with 185mph winds.
The eastern US coast remains on alert for Dorian to move in that direction.
The most recent update from the US National Hurricane Center (NHC) placed Dorian just north of Grand Bahama, home to about 50,000 people, having moved barely 20km (12 miles) in a day.
The NHC described Dorian as “stationary” with maximum sustained winds of 120mph (195km/h, marking it as a category three on the Saffir-Simpson hurricane scale.
But the NHC warned that the storm was still producing higher gusts and storm surges 10ft-15ft (3m to 4.5m) above normal, and the agency advised residents to remain in shelter on Grand Bahama throughout Tuesday.
The winds at the core of the storm were spinning so fast that the centre of the storm was collapsing on itself, causing it to expand and damage a larger area, according to the BBC Weather service.
Steve McAndrew, of the International Red Cross, told the BBC he had been involved in rescue operations for 20 years and could not recall a hurricane ever being listed as stationary.
Palm Beach county in Florida – less than 100 miles to the west – saw gusts of up to 60mph on Tuesday.
Eyewitness videos and reports painted a picture of massive and widespread flooding, with panicked families fleeing to their roofs to escape rising floodwaters.
The Bahamas Press showed video of the Rand Memorial Hospital in Freeport under water, with patients forced to evacuate. The news site also relayed calls for help from residents trapped on roofs for hours.