Hurricane Dorian has not moved much since yesterday as it has battered the Northwestern Bahamas with hurricane conditions for over 24 hours. Due to an eyewall replacement cycle and possible upwelling of cooler water, Dorian has weakened some since yesterday, but remains a powerful Category 4 hurricane. However, the eyewall replacement cycle has resulted in Dorian’s wind field expanding, which increases the chances that the United States southeast coast may receive hurricane-force winds even if the center of Dorian does not directly make landfall.

As of 11:00 p.m. EDT Monday, Hurricane Dorian was centered near 26.9°N 78.5°W, and was nearly stationary. Maximum sustained winds were 115 knots (130 mph), with an estimated minimum pressure of 946 mb. Hurricane-force winds extend approximately 45 miles outside of the center, while Tropical Storm force winds extend approximately 150 miles outside of the center. Even though Dorian has weakened, it remains a very powerful hurricane, with a well-defined eye and cold convection surrounding it. During the next 48-72 hours, Dorian should remain a powerful hurricane, with wind shear expected to remain relatively low and sea surface temperatures remain warm. However, it is a possibility that if Dorian does not begin to move to the north soon, cold water upwelling may weaken Dorian further. After 72 hours as Dorian remains close to the southeast U.S. coast, wind shear is expected to increase to above 25 knots (30 mph), while sea surface temperatures cool. As a result, Dorian should weaken below major hurricane strength around this time. Dorian should transition into an extratropical cyclone in 4-5 days, as it accelerates northeastward away from North Carolina.

Because Dorian has not moved west today, it appears unlikely that a westward motion will resume. Therefore, the chances of a Florida landfall are now low, but the scenario still cannot be ruled out entirely. Dorian should begin moving slowly northwestward some time on Tuesday morning, with a turn to the northeast expected on Wednesday as Dorian gains forward speed. Even if Dorian does not make landfall in Florida, tropical storm force winds are likely on the coast, with isolated hurricane force winds possible in the Space Coast region. It remains a distinct possibility that Dorian could make landfall in eastern North Carolina on Thursday evening, possibly in the Outer Banks region. However, the most likely scenario is that Dorian does not make landfall in the United States at all. It should be stressed that does NOT mean Dorian will safely go “out to sea”! Storm surge remains a major threat, with the region from Lantana, FL to South Santee River, SC expected to receive 4-7 feet of storm surge. Deerfield Beach to Lantana, FL is expected to receive 2-4 feet of surge. Storm surge is also possible in coastal North Carolina later this week, but no watches or warnings have been issued yet. The primary threat with Dorian will be heavy rainfall; coastal areas north of Florida are likely to receive 5-10 inches of rainfall with isolated amounts of over 15 inches possible in heavier rainbands. Coastal Florida is expected to receive less rainfall, with amounts of 4-8 inches possible with isolated 10+ inch totals in some areas. An additional 6-12 inches of rainfall is also expected in the Bahamas during the next 24 hours.