When Hurricane Dorian appeared to park itself over the Grand Bahamas and Abacos Islands for more than 24 hours, it did so because “environmental influences” were holding it in place.
“For most of the East Coast and across America, there was this huge high-pressure area,” Jhordanne Jones, a graduate research assistant at Colorado State University’s Department of Atmospheric Science, told Trade Only Today yesterday. “It backed Dorian into a corner and kept it over the Bahamas.”
That same high-pressure ridge is also to blame for Dorian’s slow movement and for the storm’s ability to maintain its strength. As of this morning, it actually gained strength and grew back to a Category 3 hurricane. Yesterday, the storm had been downgraded to a Category 2. As of 5 a.m., it was 70 miles south-southeast of Charleston and moving NNE at 8 mph.
Dorian became a named storm on August 28 and for it to still be going strong a week later is atypical. Jones said a sub-tropical ridge pressing down from the north is “really slowing Dorian at the moment.” She did say that the high-pressure system would retreat late yesterday, allowing Dorian to start moving to the north.
Jones said that the eye should remain offshore and she doesn’t expect it to expand.
“Dorian is a really compact storm,” said Jones. “It’s spread out a little since the Bahamas, but we still considerate it compact.”
Dorian is expected to remain offshore and will move up the East Coast of the United States through the end of this week. There is talk of a direct landfall around the Outer Banks of North Carolina, but much like the Carolinas experienced with Florence in 2018, the bigger concern is flooding.
“The main message at this point is to keep an eye out,” said Jones. “There is still the warm Gulf Stream that could power Dorian back up and it might sit over specific areas depending on how the environment evolves.”