The eyewall, the area of the hurricane around the eye with the strongest winds, came ashore on the central east coast in the area around Stuart late on Saturday evening, and by 1030 GMT on Sunday the eye itself was starting to move ashore.
Whipping rain around like a carwash, it delivered a record fourth hurricane strike in one season to a storm-stunned Florida.
Long before landfall - when the centre of the hurricane crosses the coastline - Jeanne's winds picked up debris and piles of tree limbs left behind by Frances' onslaught, and snapped power lines that had only just been fixed.
The storm peeled off blue tarpaulins covering roofs damaged by Frances, and huge waves pounded the Atlantic coast.
Jeanne's winds and 2.4m storm surge earlier lashed the northern Bahamas, a 700-island chain home to 300,000 people, stretching from Haiti to the Florida coast.
Jeanne, which as a tropical storm caused devastating flooding that likely killed more than 2000 people in Haiti and 31 in the Dominican Republic and Puerto Rico a week ago, was a Category 3 hurricane on the 1-5 Saffir Simpson scale of intensity.
Up to three million storm-weary residents in the state of 17 million people were told to evacuate coastal islands, mobile homes and flood-prone areas.
Many on the Atlantic coast, emboldened by having survived Frances, remained at home to the alarm of authorities who cautioned that Jeanne was a stronger storm.
This is the fourth hurricane in one
season to hit Florida
"People here are tired," said Yvonne Martinez, a spokeswoman for Brevard County emergency management.
"A lot of them decided to ride out the storm at home and didn't evacuate. That's not really a good idea. This one is scary. We're concerned that there'll be a death toll in this one."
Governor Jeb Bush sent yet another letter to his brother, US President George Bush, asking for a federal disaster declaration to speed recovery aid. Nearly 3500 National Guard troops were deployed around the strike area to respond after the storm passed.
It was the first time since record-keeping began in 1851 that four hurricanes hit Florida during the same Atlantic hurricane season, which runs from June to the end of November.
Jeanne followed the blows of Charlie, which slammed into the southwest Gulf coast on 13 August, Frances which hit the central east coast on 5 September and Ivan, which devastated the northwestern corner of Florida and the Alabama coast on 16 September.
Between them, the storms have killed 108 people in Florida and other parts of the United States, and caused up to $17.8 billion in insured losses.
In the Bahamas, residents of Grand Bahama and Great Abaco islands, both still recovering from the ravages of Frances, packed into shelters.