2:40 PM | Update on Tropical Storm Dorian with near-term prospects for intensification (not great) and potential "subtle, but important" change in the track

Discussion

Tropical Storm Dorian has weakened somewhat over the past 24 hours now with sustained winds estimated at 50 mph whereas this time yesterday the winds were about 10 mph higher. Additionally, the central pressure of Dorian has come up a few millibars (mb) in the past 24 hours to 1006 after being at 999 mb early yesterday. The movement continues to be to the west-northwest (285 degrees) at a rapid clip of 20 mph.

Looking ahead to the next couple of days, there are two things that can be said about the intensification prospects and the storm track. First, it is quite likely that intensification will continue to be inhibited by some more mid-level dry air that is still out ahead of the tropical storm. Second, the current steering winds in the lower part of the atmosphere may make a subtle change to the track from west-northwest to more due west (ie 270 degrees) or even just south of due west (e.g., 260 degrees) and while this may sound insignificant, it could result in the system heading very close to, if not right over, the Caribbean Islands of Puerto Rico and/or Hispaniola. This possible type of track over the Caribbean Islands would likely result in the further weakening or even complete demise of Tropical Storm Dorian. For weak tropical systems, the best atmospheric level to focus on for predicting future storm movement is usually between 850 mb (roughly 5000 feet) and 700 mb (10,000 feet). [The stronger the storm, the more important are the higher atmospheric winds for steering considerations]. Stay tuned.