04 September 2019

Dorian lumbers along Florida coastline, Fernand and Gabrielle form

Hurricane Dorian finally started the much-anticipated northward turn on Tuesday morning.  As of Wednesday at 9am EDT, Dorian is a Category 2 hurricane with 105 mph sustained winds, and is centered just 90 miles east of Daytona Beach FL.  Tropical storm force winds extend an average of 150 miles from the center, and hurricane force winds extend an average of 50 miles from the center.  It's moving toward the north-northwest at 8 mph.

The forecast track keeps Dorian very close to the southeast U.S. coastline through Friday. There would be a noticeable increase in wind where the western eyewall scrapes the coastline or moves inland, but even if it remains offshore, coastal flooding will be a big problem.
Although the maximum winds have been decreasing since Sunday, the storm's wind field has been expanding, and with that larger size comes a larger reach and impact from storm surge.  In fact, storm surge warnings now span from Melbourne FL up to Surf City NC, and a storm surge watch extends from there up to Hampton VA.  A peak of 5-8 feet is forecast for parts of the South Carolina coast, including Myrtle Beach. Check the latest surge guidance for a specific location on the NHC website.
Heavy rain is likely along  coastal parts of Georgia and the Carolinas through Friday, with the heaviest totals expected in the Charleston to Wilmington area. There are several long radar loops available at http://bmcnoldy.rsmas.miami.edu/tropics/radar/ to monitor the rainfall associated with Dorian.

Elsewhere in the Atlantic, the disturbance that was in the western Gulf of Mexico is now Tropical Storm Fernand, and the tropical wave west of Cabo Verde is now Tropical Storm Gabrielle.  There is still a decent chance that the disturbance near Bermuda and one exiting the African coast will form too in the coming days. None of these are an immediate or foreseeable threat to the U.S. Fernand will dump some locally heavy rain in extreme northeastern mexico but dissipate

This surge in activity across the basin is pretty characteristic of early September -- this is the time of year when environmental conditions favor hurricane formation across much of the basin.  The next names on the list are Humberto and Imelda.  Imelda is a new name on this list; it replaces Ingrid which was retired after its destructive run in 2013.

In terms of ACE (Accumulated Cyclone Energy), the 2019 season rapidly made up its deficit with Dorian, and is now at 116% of average for this date, using the past fifty years as the climatology.

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