Residents of the Miami area and the Florida Keys streamed north in packed vehicles Friday morning, anxiously rushing to dodge Hurricane Irma as the deadly Category 4 storm took aim at the state's eastern coast after devastating the Caribbean.
The dramatic mass exodus from South Florida could turn into one of the largest evacuations in US history, CNN senior meteorologist Dave Hennen said. Miami-Dade, Broward and Palm Beach counties are home to about 6 million people combined.
But the clock is ticking for those who haven't left yet, officials warned.
"Get inland for safety," Florida Gov. Rick Scott said.
"Based on what we know, the majority of Florida will have major hurricane impact and deadly winds. We expect this along the entire east coast and west coast," the governor said at a news conference. "All Floridians should be prepared to evacuate."
Thousands of motorists braved clogged roads, backups and slowdowns to get out. Some drivers waited for hours at gas stations, some of which ran out of fuel. The Florida Highway Patrol escorted fuel tankers so they could reach and resupply gas stations, the agency reported.
Travel hot spots included Interstates 95 and 75, and the Florida Turnpike. Troopers monitored roadways, stepping in to help after fender-benders and with disabled cars and trucks.
Mandatory evacuation orders covered parts of Miami-Dade County, Broward County east of US 1, Palm Beach County, low-lying parts of Brevard County, coastal and low-lying areas of Jacksonville and Duval County, and Monroe County, home to the Florida Keys.
The evacuation of Miami-Dade County was the largest in the county's history, with an estimated 660,000 people asked to leave, Mayor Carlos Gimenez said.