Hurricane Dorian to become dangerous Category 4 storm prior to making US landfall
By Courtney Spamer, AccuWeather meteorologist

AccuWeather Chief Video Meteorologist Bernie Rayno says Dorian is getting better organized as it moves away from the Caribbean.

As Dorian spun into the warm, open waters of the Atlantic Thursday, concern grew about the storm’s projected path towards the United States, where it could strike as a major hurricane over the upcoming holiday weekend.

The National Hurricane Center said during its 11 a.m. advisory that the storm was about 220 miles north-northwest of San Juan and 370 miles east-southeast of the Bahamas. The storm, still packing maximum sustained winds of 85 mph, was moving at 13 mph as it entered the open — and warmer — waters of the southern Atlantic.

As Dorian, the second hurricane of the Atlantic season, tracks north of the Bahamas later this week, it is expected to reach Category 4 hurricane strength before approaching the southeastern United States coast.

A major hurricane has the strength of a Category 3 or greater. A Category 4 hurricane has maximum sustained winds of at least 130 mph.

“The strengthening to a major hurricane is projected to occur while making a more westward turn toward the northern Bahamas this weekend,” According to AccuWeather Senior Meteorologist Alex Sosnowski.

“With Dorian forecast to pass over extremely warm water of the Gulf Stream, where the water is rapidly replaced by more warm water, you have to be concerned that a Category 5 storm is on the table before reaching the U.S. coast,” Sosnowski said.

A Category 5 hurricane has maximum sustained winds of at least 157 mph.

On Wednesday, Florida Gov. Ron DeSantis declared a state of emergency to give officials enough time to prepare for the storm and urged all Floridians on the state’s east coast to “have seven days of supplies, prepare their homes and follow the track closely.”

Recall that Hurricane Andrew, from August 1992 experienced rapid strengthening over the Gulf Stream prior to making landfall in South Florida. Andrew reached Category 5 status prior to making landfall.

The storm made a shift to the north on Wednesday causing its center to regenerate northeast of Puerto Rico and putting forecasters on alert for development of the Atlantic’s first major hurricane of the 2019 season.

The hurricane brought waves of heavy rain to Puerto Rico and parts of the U.S. and British Virgin Islands on Wednesday after it battered portions of the Lesser Antilles on Tuesday. While Dorian’s eye wasn’t yet visible on satellite imagery Wednesday afternoon, it was easy to spot in a radar loop showing the storm passing by Puerto Rico.

On Wednesday evening, lightning was detected in the eye of Hurricane Dorian by the GOES-16 weather satellite as it passed northeast of Puerto Rico. When lightning is detected in the eye of a hurricane, it is usually an indication of rapid strengthening.

“Dorian shifted to the north as it traveled over warm open waters, allowing it to undergo rapid strengthening,” said AccuWeather Hurricane Expert Dan Kottlowski of the storm’s rapid intensification.

As this happened the storm moved away from the core of a vast area of dry air over the central Caribbean.

The longer the amount of time the tropical system spends over the warm, open waters of the Atlantic, away from major land areas, the greater the chance of significant strengthening.

Cruise and shipping interests from Florida to the waters just north and east of the Bahamas should prepare for hurricane conditions with mountainous seas and high winds.

“People on Abaco and Grand Bahama should prepare for major hurricane conditions to spread westward over the islands spanning Saturday night and Sunday,” Sosnowski said.

“While the exact track of Dorian will determine how severe conditions get on these two major islands in the chain, Cornishtown, Bahamas, near the northernmost point on Abaco could be a hard-hit area,” he added.

Some of the far northern islands of the Bahamas will be significantly impacted while the majority of the others will get barely a breeze and a little rain.

Dorian track 4
At this time, lesser impacts are expected across the southern half of the Bahamas, farther from the center of Dorian.

With several days over the open waters of the Atlantic still to go, the exact track of Dorian for the weekend and beyond is not set in stone.

As a precaution, officials have moved this Saturday’s Florida State/Boise State football game from Jacksonville, Florida, to Tallahassee, Florida, at noon the same day.

Other factors in the atmosphere through the weekend, from a high pressure over Bermuda to a non-tropical storm in the central U.S., could open up the possibility for potential impacts in locations from South Florida to the Outer Banks.

This could influence whether Dorian tracks westward into Florida or slows before reaching the Florida coast and makes a turn to the north.

“If Dorian does slow and turn to the north, impacts in the Carolinas would be much more significant while Florida would be spared from major damage,” Douty added.

“Because of the wide range of possibilities, the wind, surge and rainfall impacts expected from Dorian over the northern Bahamas and Florida are highly uncertain at this point,” added Kottlowski.

At this time, AccuWeather believes a landfall over the middle of the Atlantic coast of Florida is most likely and is in the center of cone of the AccuWeather.com forecast Eye Path™.

By the time Dorian reaches the U.S., the overall size of the storm may be somewhat larger and its impact will reach farther, when compared to the compact system in the Caribbean. This could bring a wider range of impacts from southern Florida to the Georgia and South Carolina coastlines.