Dorian sat just north of Grand Bahama, about 100 miles east of Florida’s West Palm Beach, the National Hurricane Center said in a 3 a.m. advisory. While its winds continue to weaken as it widens out, the storm has inflicted huge damage, killing five on one island, according to Prime Minister Hubert Minnis, who called the destruction a “historic tragedy.”

Even if the U.S. mainland dodges a head-on blow as the hurricane follows a track up the east coast over the next few days, that would still bring it “dangerously close” to Florida through Wednesday, according to the NHC. It’s threatening to inundate coastal communities with rain and rising sea levels. In Georgia and the Carolinas, coastline residents are being told to evacuate.

Georgia Governor Brian Kemp and South Carolina Governor Henry McMaster ordered residents in coastal areas to flee before Dorian arrives, according to state web sites. North Carolina Governor Roy Cooper said residents in his state should heed evacuation orders from local leaders.

“We know that these evacuations are inconvenient, difficult and sometimes costly,” Cooper said in a televised statement. “But we must realize the potential deadly cost of refusing to evacuate when told.”

A slow north-westward motion is expected to occur early Tuesday, according to the NHC. The hurricane will then move close to Florida’s east coast late Tuesday through Wednesday evening, very near Georgia and South Carolina coasts Wednesday night and Thursday, and near or over the North Carolina coast late Thursday.

While the current forecast keeps Dorian’s center offshore, forecasters are keeping a close eye for changes, according to Ken Graham, the hurricane center’s director. “It doesn’t take much, a little wobble, a little wiggle and you have hurricane-force winds on shore,” he said in a Facebook update.

In the meantime, Dorian continues to devastate Grand Bahama, one of the nation’s northernmost islands, and has caused widespread flooding in many of the islands of the northwest and central Bahamas, the National Emergency Management Agency said in a bulletin Monday.

Parts of the northern Bahamas are in the “midst of a historic tragedy” Prime Minister Minnis said in a post on Twitter. Based on reports out of Abaco, one of the first islands to be hit, “the devastation is unprecedented,” he said earlier.

Dorian will cause at least $25 billion of insurance losses, according to analysts at UBS Group AG, the costliest of any natural disaster since 2017. Depending on whether it hits the eastern coast of Florida in the next few days, the storm could cost as much as $40 billion, they said.

An 8-year-old boy drowned in Abaco, his grandmother told local television station Eyewitness News. Authorities have not confirmed the death, the station said. The Bahamas Press said that Grand Bahama International Airport was under 5 feet of water.

The damage to some of the region’s large tourist hotels will likely hit revenue in a country where tourism accounts for about half of gross domestic product, said Andrew Stanners, investment director for Aberdeen Standard Investments, which owns the nation’s dollar bonds. The Bahamas has recently taken “strident steps” to improve government finances, which leave it better placed to repair the devastation, he said.

There are also two major petroleum terminals in the Bahamas. Buckeye Partners LP operates a large crude and refined products terminal at Freeport, roughly 100 miles from the Florida coast, and Equinor ASA has a terminal in nearby South Riding Point. The Buckeye terminal has a capacity of 26 million barrels of crude, gasoline and diesel, the Equinor terminal has a storage capacity of 6.75 million barrels of crude and condensate.

Buckeye media contacts didn’t respond to multiple emails seeking comment. Equinor was in the process of shutting its terminal ahead of Dorian, the company said.

The Bahamian government was preparing orders to allow donated relief supplies to move quickly to areas that need it most, local Eyewitness News reported.

In Florida, storm surge warnings now extend up the coast into Georgia and forecasters say the ocean, pushed by Dorian, could start inundating the shoreline and rivers by Tuesday.

In a briefing, Florida Governor Ron DeSantis said Florida utilities have assembled 17,000 personnel to help restore power quickly as needed. He said 72 nursing homes and assisted living centers along the coast have been evacuated, and hospitals were starting to evacuate as well.

Meanwhile, airlines have canceled 1,300 flights within, into and out of the U.S. today, according to FlightAware, a Houston-based airline tracking company. Fort Lauderdale and Orlando are the two hardest hit airports.

Mandatory evacuations have been ordered in parts of Florida, Georgia and South Carolina, including for the Mar-a-Lago club owned by U.S. President Donald Trump, which he often uses as a “Winter White House.” While Dorian is forecast to stay offshore there will be extensive damage along the coast from storm surge, high winds and flooding rains.

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