Hurricane Matthew slightly grew stronger early Tuesday and shifted closer to Florida, according to the National Hurricane Center in Miami.

The Category 4 hurricane headed toward Haiti with top sustained winds near 145 mph, up from 140 mph earlier, the hurricane center said. It was moving northward at 8 mph and was nearing the southwest peninsula of Haiti.

"The threat to Florida and the southeastern U.S. coast has increased," the National Hurricane Center said. Life-threatening rain and storm surge was expected in parts of Haiti by early Tuesday morning.

A hurricane warning remains in effect for all of Jamaica, all of Haiti and portions of Cuba and the Bahamas.

The updated forecast tracked Matthew heading west closer to Florida, which also is in a state of emergency. Matthew is expected to reach Florida later this week.

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North Carolina Gov. Pat McCrory declared a state of emergency for central and eastern parts of the state.

Forecasters offered basically two very different scenarios for Matthew after it decimates the Caribbean: Either a direct hit, anywhere from Florida to Maine, or a miss, with the storm sliding up the coast but never making landfall. Which scenario plays out depends on the path the storm takes.

The hurricane is expected to weaken slightly over the course of the week. At the very least, Matthew could cause significant beach erosion along the Atlantic coast, as well as dangerous conditions for surfers and small crafts, according to Accuweather.

The death toll rose to three Monday when the body of a fisherman was found in rough waters off the south coast of Haiti, the Associated Press reported, citing the civil protection agency. One man died Friday in Colombia, and a 16-year-old in St. Vincent and the Grenadines was killed Sept. 28 when the system passed through the eastern Caribbean.

Contributing: Doyle Rice, USA TODAY.