Updated: 3:35 p.m. EDT

(Bloomberg) -- With top winds of 140 miles (225 kilometers)per hour, Hurricane Matthew could be the strongest storm to hit theU.S. since 2005, and among the costliest as it bears down onFlorida’s East Coast.

The Category 4 storm is expected to make landfall near West PalmBeach and Melbourne overnight and then track north along theAtlantic coast racking up as much as $50 billion in economiclosses.

At least 1.5 million people have been ordered to flee its pathwith evacuations under way in Georgia and South Carolina asforecasts call for the storm to continue north into theweekend.

The U.S. hasn’t been hit by a major hurricane with winds of 111miles per hour or more since Wilma struck Florida in October 2005.Katrina, also in 2005, caused about $154 billion in damage, makingit the costliest in U.S. history, according to the National Oceanic andAtmospheric Administration. Matthew has already devastated theCaribbean, killing at least 108 people on Haiti and postponing thecountry’s presidential election set for Sunday.

“They have never had a major hurricane hit from Cape Canaveralnorthward to Georgia in the past century,” said Jeff Masters, co-founder of Weather Underground, inAnn Arbor, Michigan. “It is certainly the most dangerous one sinceSandy, and the most dangerous for Florida since Wilma.”

Life-threatening winds

Matthew’s top winds jumped to 140 miles per hour, up from 125 mph,as it moved across the Bahamas about 125 miles east-southeast ofWest Palm Beach,, the U.S. NationalHurricane Center said in an 2 p.m. advisory.

People caught without shelter in the hardest hit areas facelife-threatening winds, damage to buildings, roads andbridges, and the loss of power and communications that couldrender places uninhabitable for weeks or months, according tothe National Weather Service. The storm surge could reach 9 feet insome places.

NextEra Energy Inc.’s Florida Power & Light utility, thestate’s largest, said as many as 1.2 million customers could losepower. More than 90 percent of flights using Miami InternationalAirport have been canceled, according to a statement. Most airlineswere expected to suspend operations at noon. Matthew has shut theBuckeye oil terminal in Freeport, Bahamas, and could disruptpetroleum shipments along the U.S. East Coast. Orange crops areseen suffering little damage.

Economic losses

Depending on Matthew’s exact track and strength, damages couldreach $50 billion, according to Chuck Watson, a disaster modelerwith Enki Research in Savannah, Georgia. Bloomberg Intelligenceanalysts Jonathan Adams and Jeffrey Flynn, citing Kinetic Analysisdata, predict $35 billion in economic losses.

“The highest reasonable estimate is $50 billion,” Watson said.“And $25 billion or less is most likely depending on exactly howclose to the coast and how strong the storm is at landfall. It’sgot a really good shot at the top 10,” costliest storms.

View our full coverage on disaster risksand recovery for Hurricane Season 2016

Twelve U.S. power generators, including two nuclear plants, arein the storm’s path, according to data compiled by Bloomberg. Onenuclear facility, NextEra’s Turkey Point in south Florida, is justoutside the storm’s projected path. NextEra and Duke Energy Corp.said they would shut their reactors hours ahead of the onset ofhurricane-force winds.

Worst case

The key to how much damage Matthew causes will be its track as thestrongest winds extend about 60 miles from its center, the NationalHurricane Center said.

“I would say off the top it is way too premature to quantifylosses,” Steve Bowen, a director and meteorologist withAon Benfield in Chicago, said by telephone.“Any slight deviation to the east or west could conceivably meanseveral billion dollars of damage.”

The worst case would be for Matthew’s eye, with the strongestwinds and highest storm surge, to track along a large stretch ofFlorida’s coastline, said Masters. There is also a chance Matthewcould wobble, leaving the worst of the storm out at sea, he said.Hurricane Floyd in 1999 followed a similar path as Matthew, butnever came ashore in Florida.

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