We are nearing the peak of the Atlantic hurricane season, and fittingly there is a tropical cyclone threatening the mainland United States.
Dorian is a strengthening tropical storm, currently located over the eastern Caribbean Sea moving in a general northwest direction. The storm will near or make landfall on either Puerto Rico or the Virgin Islands later today and into early Thursday, bringing heavy rain, gusty winds, and storm surge. Since Dorian is still intensifying and becoming more organized, the National Weather Service has issued a Hurricane Watch for these islands due to potential last-minute strengthening prior to impact. Based on the latest National Hurricane Center (NHC) forecast, maximum sustained winds are expected to reach 70 mph — if not greater — near the center of the storm. This will cause tree damage and power outages. There is also the risk for 6-8 inches of rainfall across parts of the region, which may lead to flash flooding. Dorian does not have to be a hurricane to bring flooding. Martinique has already experienced terrible flooding on Tuesday when the storm was producing top winds of only 50 mph.
Dorian will then move north of the Greater Antilles by Thursday morning. Dorian’s interaction with Puerto Rico will be very important to watch — even if there isn’t a direct impact – as it could change the storms internal structure. The tall mountains of Puerto Rico can affect the low-level circulation of tropical cyclones, causing them to weaken or even fall apart completely.. So what happens over the next 24 hours will tell a lot about what kind of storm the US may be dealing with this weekend.
An upper-level low located to the south and west of Dorian will continue to steer the tropical storm to the northwest, bypassing the southern and central Bahamian islands. By Saturday, however, we’ll begin to see Dorian take a more westerly turn as the upper-low drifts to the south and a high pressure builds in from the north, steering the storm toward the US. As of now, a landfall on the US is likely but there is still the chance the storm will be able to escape out to sea if there is a weakness in the high pressure.
From South Florida through South Carolina, landfall is possible during the Sunday – Monday timeframe. The NHC is now forecasting Dorian to strengthen into a Category 2 hurricane on its approach to the Southeast due to low wind shear and very warm sea surface temperatures. Dorian is also expected to grow in size as it strengthens and gains in latitude.
If you live along the Southeast coast, especially in the areas mentioned above, have a hurricane plan in place. It is still early to tell what the eventual outcome of this storm will be but it is always best to be prepared instead of waiting for the storm to hit. The models have been trending with a more northward track but more shifts in the track are expected.
Stay with WeatherOptics for continuous updates on Dorian online and on social media.