MIAMI — The U.S. National Hurricane Center announced around 5 p.m. Monday that Hurricane Irma has become a Category 4 with winds 140 mph and early models showing Irma head toward south Florida Saturday morning.

Hurricane warnings are in effect for portions of the Leeward Islands as tropical-storm force winds are expected to arrive in the area by late Tuesday.

Hurricane watches for Puerto Rico and the Virgin Islands were upgraded to warnings Monday night as Irma's wind speeds increased to 145 mph.

"Irma is a very serious threat all across the northern Caribbean and Bahamas, and an increasing threat to Florida, possibly including central Florida. Don't wait to come up with a hurricane emergency plan. Know if you're in a potential coastal evacuation zone," said certified Chief meteorologist Tom Terry.

Islands at the eastern end of the Caribbean Sea are making preparations for approaching Hurricane Irma, which could threaten the area Tuesday.

The NHC said the center of the storm could near that region late Tuesday. It said islands farther north, including the U.S. Virgin Islands and Puerto Rico, should monitor the progress of the storm.

Officials said Irma had maximum sustained winds of 130 mph on Monday.

Irma could directly impact Hispaniola, the Turks and Caicos, the Bahamas and Cuba as a hurricane later this week, according to NHC.

State of Emergency:

Florida Gov. Rick Scott has declared a State of Emergency as Hurricane Irma approaches Florida. Although it's still unclear the hurricane's path, by making the state declaration, it provides federal, state and local governments resources and time to get ready just in case.

"In Florida, we always prepare for the worst and hope for the best and while the exact path of Irma is not absolutely known at this time, we cannot afford to not be prepared. This state of emergency allows our emergency management officials to act swiftly in the best interest of Floridians without the burden of bureaucracy or red tape," Scott said in a statement.

"It looks like there will be an increased chance for Florida to be impacted by Irma later this week," Certified meteorologist Ebon Deon said. "However, it's important to note it's too early to determine specifics on any direct impacts to the U.S."

Deon said that residents should prepare for the storm "just in case."

"We will continue to monitor Irma over the next few days as there could be changes along the way," Deon said. "We are in the peak hurricane season and it’s wise to have your hurricane kits and plans in order regardless."

Download the free WFTV weather app and watch Channel 9 Eyewitness News for regular updates on the storm's progression.

The Associated Press contributed to this report.

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