Hurricane Dorian, now Category 4, continues its path toward Florida States of emergency have been issued in every county in Florida.

Hurricane Dorian has strengthened to a Category 4 storm with 130 mph winds as Floridians brace for the extremely dangerous storm to hit.

Dorian is forecast to make landfall along Florida's east coast on Tuesday. But because the hurricane is slow-moving, it will likely be a multi-day storm with prolonged periods of hurricane conditions, storm surge and heavy rain in Florida and parts of the Southeast.

Florida is "looking at a storm that can produce life-threatening storm surge and major hurricane-force winds," Gov. Ron DeSantis said at a Friday evening briefing. "There is a danger to your life if you remain."

Mandatory evacuations have been ordered for low-lying areas in Brevard and Martin counties starting Sunday morning, with shelters opening at the same time.

Forecast to approach Florida with winds of 140 mph, Dorian, should it make landfall at those wind speeds, would become just the ninth hurricane to do so, dating back to 1851.

Dorian could be the biggest hurricane to hit the Miami area since Hurricane Andrew in 1992.

The latest forecast shows Dorian making landfall early Tuesday morning near West Palm Beach, but different models show the hurricane taking different paths after landfall.

Most models are predicting Dorian will make a sharp turn north.

If Dorian continues on that track, Orlando and Jacksonville may see heavy rain, gusty winds and significant flooding. Dorian would then move north to coastal Georgia and South Carolina, where rain, storm surge and flooding is a threat.

Other models forecast a path to the west across Florida.

Dorian is a relatively small hurricane, leaving a lot of uncertainly -- any change in the atmosphere can move the storm in a different direction or change its speed.

"No matter where the hurricane makes landfall, it could impact the majority of Florida," Peter Gaynor, acting administrator of the Federal Emergency Management Agency (FEMA), told "Good Morning America" on Friday.

By Saturday, Dorian is likely to reach winds of 130 mph.

"The clock is ticking and now is the time for residents of Florida, south Georgia to make preparations," Gaynor said. "Don't take this storm lightly."

President Donald Trump on Friday approved an emergency declaration for Florida, where a state of emergency was issued in every county.

Residents on Florida's east coast are waiting in massive lines to stock up on food, water and gas, and scrambling to board up their homes and businesses.

The University of Florida is closing its campus and canceling classes for Tuesday.

Orlando International Airport is planning to stay open through Sunday and then stop commercial flights at 2 a.m. Monday.

"We urge all Floridians to have seven days' worth of food, medicine and water," Gov. DeSantis said earlier Friday. "This is potentially a multi-day event where it'll churn slowly across the state."

"If you're in an area that has an impact from this storm, you should assume you're going to lose power," he said. "If you're in an area that flooded during Hurricane Irma [in Sept. 2017] and you're impacted by this, you should assume that you're going to see flooding again after this storm. So be prepared."

The biggest threat will be storm surges -- ocean water pushed to shore by hurricane winds. One to 2 feet of rain is forecast for the east coast of Florida, and flash flooding is expected.

"If you're in an evacuation zone and you're ordered to evacuate, please do so," the governor said.

Trump said his administration is "working very, very hard" and is prepared to provide aid and assistance.

First, Dorian is forecast to move across the northern Bahamas on Sunday as a Category 4 storm with 130 mph.

Storm surge in the Bahamas could reach up to 15 feet and many islands are already under evacuation orders.

"Let me be extremely clear: Those who refuse to evacuate place themselves in great danger from this very powerful and potentially life-threatening hurricane," Bahamas Prime Minister Hubert Minnis said Friday. "Do not be foolish and try to brave out this hurricane."