Power outages were expected across large parts of Florida as Hurricane Idalia made landfall in the Florida Big Bend as a Category 3 storm around 7:45 a.m. ET Wednesday.

Maximum sustained winds were estimated to be about 125 mph, according to the National Hurricane Center.

"Catastrophic storm surge and destructive winds are nearing the Florida Big Bend region," the update said. "While Idalia should weaken after landfall, it is likely to still be a hurricane while moving across southern Georgia, and near the coast of Georgia or southern South Carolina late today."

Florida Gov. Ron DeSantis declared a state of emergency in 49 of the state's 67 counties across the northern half of the state from the Gulf Coast to the Atlantic Coast. He urged those in evacuation zones to do so immediately.

"Now's the time to do it," DeSantis said during a Tuesday night news conference. "If you wait much longer . . . the weather's going to start getting nastier and nastier."

In the 5 a.m. National Weather Service update, Idalia was reported to be speeding north-northeast at 18 mph. Idalia could continue to strengthen before it reaches the coast later this morning, the update warned.

The National Weather Service described the storm as an "unprecedented event," saying no major hurricane − Category 3 or higher − had ever slammed the Big Bend's Apalachee Bay.

Stay up to date with power outages across the state with our USA TODAY's power outage map.

LIVE UPDATES:'Catastrophic' storm surge possible as Hurricane Idalia nears Florida landfall

POWER OUTAGE MAP:See Naples, Collier County power outage map as Hurricane Idalia impacts Florida

Florida power outage map

As of 11:10 a.m. ET, there were over 268,000 reported power outages in Florida, mostly in the northern part of the state, according to USA TODAY's power outage tracking database.

Leon County had over 50,000 reported outages while Suwannee and Columbia counties each had over 23,000 reported outages.

Wakulla County, Florida power outage map

Leon County, Florida power outage map

Suwannee County, Florida power outage map

Columbia County, Florida power outage map

Contributing: John Bacon & Christopher Cann, USA TODAY