Tropical Depression 4 has now been upgraded to Tropical Storm Dorian in the eastern part of the Atlantic Ocean. This tropical wave has become very well organized over the past 24 hours despite encountering some dry air in the middle part of the atmosphere. There is now quite an impressive circulation center associated with the storm and perhaps even an eye trying to form. The 11am measurements have sustained winds at 50 mph, gusts to 65 mph, and movement to the WNW at 20 mph.
While the tropics have been somewhat quiet in recent days, having the fourth named storm on this date is about one month ahead of the average date over the past fifty years (August 23rd), and it is quite rare for a storm to form this far east in the Atlantic this early in the season. In fact, there is a report that since 1851 only three other storms reached tropical storm status this far east in the Atlantic so early in the season (last one was Bertha in 2008). None of the first three tropical storms this season (Andrea, Barry, Chantal) ever reached "hurricane" status. There has not been a major hurricane strike (ie category 3, 4 or 5) in the US since the the record-breaking year of 2005. The 7-year period from 2006-2012 without a major hurricane landfall in the US is the longest period since 1851.
Looking ahead, the next 24-48 hours will be crucial for Tropical Storm Dorian as it’ll encounter some mid-level dry air and slightly cooler waters, but chances are increasing that it will survive this meeting. Models are generally in agreement on moving Dorian to the WNW over the next five days or so and it very well could be near the Bahamas or western Caribbean Islands in about a week or so. Stay tuned - all eyes on the east coast should monitor this new storm.