Hurricane Milton made landfall around 8.30 p.m. on Wednesday (0030 GMT on Thursday) as an “extremely dangerous Category 3’’ storm, hitting the Siesta Key on the west coast of Florida.
The National Hurricane Centre reported the development.
The storm winds were up to 193km per hour, meterologists said.
The storm resulted in President Joe Biden postponing his trip to Germany and Angola, which was to start on Thursday.
Milton had been Category 5 storm as it was moving toward Florida from the Gulf of Mexico.
This was downgraded to Category 4 and being lowered to level 3 before it hit.
U.S. Secretary of Homeland Security Alejandro Mayorkas described the situation on CNN as a matter of life and death.
Milton is now expected to move from the Gulf Coast of Florida across the state toward the Atlantic Ocean.
Severe destruction is also expected beyond the coasts.
Before the hurricane arrived, tornadoes were raging in parts of Florida.
Water levels rose rapidly as strong winds drove seawater inland.
Meteorologists predicted that it could become one of the most dangerous storms in the state’s history.
In addition to extreme wind speeds, heavy rainfall and dangerous storm surges are expected, which could cause widespread flooding.
Millions of people were urged leave. There were reports of traffic jams and petrol shortages.