The storm's top sustained winds decreased slightly to 280km/h while it spun along Grand Bahama island in what forecasters said would be a daylong assault.
Residents of the Abaco Islands closest to the storm were warned to "seek elevated shelter immediately", as U.S. forecasters predicted a towering storm surge of 18 to 23 feet (about 5.5 to 7 meters).
The storm - the strongest anywhere on the planet this year - made landfall Sunday afternoon on the southern end of the Bahamas' Elbow Cay, which runs along the east coast of Great Abaco.
NASA, the NHC and the National Oceanic and Atmospheric Administration are using satellites in orbit and U.S. Air Force flights through the eye of Hurricane Dorian itself to track the storm's progress. A hurricane watch was issued for Volusia County.
Even though it's expected to stay well offshore of South Florida, there is a possibility that winds over 40 miles per hour could affect Broward County, so a tropical storm watch is in effect for the area.
The president posted, "In addition to Florida - South Carolina, North Carolina, Georgia, and Alabama, will most likely be hit (much) harder than anticipated".
Many models show the storm staying just off Florida's coast Tuesday and then skirting the coasts of Georgia and North and SC.More news: Chargers, Melvin Gordon's extension talks suspended until after 2019 season
More news: Houston Rockets, Eric Gordon agree to 4-year contract extension, report says
More news: Cowboys Finalizing Long-Term Contract With Ezekiel Elliott
The NHC said Dorian had become "the strongest hurricane in modern records for the northwestern Bahamas".
Dorian is a powerful but small storm with hurricane force winds Sunday only extending 29 miles to the west, but they are expected to grow a bit.
"We're looking at a track - and this is just the center - that's only 30 or so miles offshore", Borowski said.
"The coordination is there and it's something that makes you proud, the way the state of Florida handled this", Yoho said.
Hurricane center forecasters predict 4-7 feet of storm surge from Jupiter Inlet to the Brevard/Volusia county line, and 2-4 feet from north of Deerfield Beach to Jupiter Inlet.
Yachts lie capsized in harbours after hurricane Dorian hit the Bahamas on Sunday.
In the days between the landfalls of Hurricane Irma and Maria, he said he "never even knew" they existed and said days later that "people (in Puerto Rico) had never seen anything like" the storm. Fluctuations will likely continue over the next 24 hours, but Dorian is expected to remain a powerful hurricane. The new moon is causing high astronomical tides during the times of high tide.
"Do not be foolish and try to courageous out this hurricane", Bahamanian Prime Minister Hubert Minnis said at a press conference Friday.