FORT LAUDERDALE, Fla. _ Hurricane Matthew returned to Category 4 strength Thursday morning and could be producing "extremely dangerous" sustained winds of 145 mph by the time it approaches South Florida later Thursday, the National Hurricane Center said.
An Air Force Hurricane Hunter plane detected sustained winds of 140 mph, as the storm came within 180 miles of West Palm Beach, according to the 11 a.m. advisory from the National Hurricane Center.
But the odds of the storm's core passing over Broward or Palm Beach counties appeared to decline. The latest forecast cone, showing possible paths for the storm's center, shifted east, indicating a reduced chance of a direct hit on those counties. Both counties remain at risk, and even a near-miss would bring hurricane-force winds.
Major hurricane-force winds, which means speeds of at least 111 mph, are expected Thursday night in Palm Beach County and possibly Broward County, with the northeast part of Broward at highest risk in that county, the weather service said.
Palm Beach County can expected hurricane-force winds from 9 p.m. Thursday to 6 a.m. Friday, the National Weather Service said. Although Broward is less likely to see hurricane-force winds, if they do arrive it could be from 9 p.m. to 3 a.m.
Tropical force winds would arrive earlier and stay later. Palm Beach County can expect tropical-force winds from 3 p.m. Thursday through 8 a.m. Friday, Broward County from 3 p.m. Thursday to 3 a.m. Friday, and Miami-Dade County from 3 p.m. Thursday to 1 a.m. Friday.
The storm had previously been forecast to reach a maximum sustained wind speed of 130 mph as it neared South Florida. But now, as satellite photos showed the storm becoming better organized, with the reemergence of a distinct and narrow eye, the hurricane center said it could produce winds of 145 mph.
"Right now the main concern for South Florida continues to be the threat of major hurricane-force winds, particularly across portions of Palm Beach County," said Pablo Santos, meteorologist in charge at the National Hurricane Center, said Thursday morning. "We're talking about the threat of widespread to potentially locally devastating impacts across those portions of the county."
Broward County officials urged all drivers off the roads by 1 p.m. The driving curfew is not mandatory, but the county is strongly advising against leaving home Thursday afternoon.
About 150,000 people were ordered evacuated in Palm Beach County Wednesday night, as the storm's projected course shifted closer to South Florida. The evacuation order, which will not involve the forcible removal of anyone, applies to residents of barrier islands, mobile homes and low-lying areas. Broward announced a voluntary evacuation for the beach, mobile home residents and those in low-lying areas.
Florida Gov. Rick Scott urged residents of evacuation zones to leave immediately.
"Time is up," he said in a statement Thursday morning. "You have to evacuate now if you are in an evacuation zone. To everyone on Florida's east coast, if you are reluctant to evacuate, just think of all the people the Hurricane has already killed. You and your family could be among these numbers if you don't take this seriously."
A flood watch has been issued for Palm Beach County that will be in effect until Friday afternoon.
At 8 a.m., the storm was 215 miles southeast of West Palm Beach, producing winds of 125 miles per hour, up from 115 miles per hour overnight.
The Palm Beach County evacuation order came as the National Weather Service raised its estimate that Palm Beach County could experience hurricane-force winds to 50 percent and the National Hurricane Center warned of "life-threatening" storm surge from northern Palm Beach County up the coast.
Gov. Scott activated another 1,000 members of the Florida National Guard, bringing the total to 2,500. He announced a suspension of tolls on Florida's Turnpike and other roads in the affected areas.
"Based on the most recent forecast I received from the National Hurricane Center, the eye of Hurricane Matthew is going to be much closer to Florida," Scott said. "There is still time to evacuate. Get out now if you are in an area with evacuations. If you make a decision not to leave before the storm, we cannot send someone to save you because you made a bad decision."
The storm's forecast path placed the central Florida coast near the center of the cone of possibilities for the storm's core. But the cone shows much of the southeastern United States at risk of a direct hit, from South Carolina to northern Miami-Dade County.
The projection also increased the disturbing possibility that somewhere off Georgia or the Carolinas the storm could loop to the south and make another run at South Florida next week.
Broward and Miami-Dade counties announced voluntary evacuations. All counties opened emergency shelters. Delray Beach announced a curfew from 6 p.m. Thursday to 6 a.m. Friday.
Fort Lauderdale-Hollywood International Airport announced it would close at 10:30 a.m. Thursday. Dozens of flights were canceled there and at Miami International Airport. Palm Beach International did not announce cancellations but said travelers should check with their airlines.
President Barack Obama went to the headquarters of the Federal Emergency Management Agency Wednesday to discuss preparations for the hurricane. He said supplies and response teams have been pre-positioned in Florida, Georgia, South Carolina and North Carolina.
"If there is an evacuation order in your community, you need to take it seriously," the president said.
Although Matthew is not expected to produce rain comparable to the torrents dumped on Haiti, the storm could bring several inches to some areas.
To make room for the rain to drain off land, the South Florida Water Management District, which operates the region's main drainage system, has lowered canal levels throughout the region.
"The system is poised and in a good position," said John Mitnik, the district's chief engineer.
Palm Beach County opened eight shelters.
The Coast Guard closed Miami, Miami River, Port Everglades, Port of Palm Beach and other southeast Florida ports. The Coast Guard set Port Condition Zulu, which establishes a safety zone around the ports, prohibiting traffic in or out without permission and any ship-to-shore activities.
There is a second storm in the tropics: Tropical Storm Nicole is spinning about 400 miles south of Bermuda with maximum sustained winds of 70 mph. There are no watches or warnings linked to Nicole. Forecasters say Nicole has a "slow and meandering motion" toward the northwest and is not expected to strengthen Thursday or Friday.
