Well, it’s been a busy afternoon in the tropics!  While the remnants of Fay continue to spin over the Southeast, the impressive tropical disturbance over the eastern Caribbean Sea, rapidly developing into Tropical Storm Gustav this afternoon.  

Gustav this evening is a strong tropical storm.  A small pulsing down of the thunderstorms is being observed this evening, but given the favorable atmospheric conditions (no shear, no dry air, warm sea surface temperatures) I think we will see a continuation of intensification over the next 24 hours.  I firmly believe Gustav will become a category 1 hurricane before moving through western Haiti.  

The question is where will Gustav go after Wednesday?  The model guidance has little in the way of agreement on the track of Gustav after Wednesday.  Some models taking Gustav well south of Cuba to others moving Gustav over the Bahamas and everywhere in between.  

Lets take the model result out of the discussion for a second and look at what we have developing and what all the models agree with.  All the models agree that a ridge of high pressure will build over the Bahamas and over Florida at 850 MB to 500 MB.  All models agree that a trough will dig into the western Gulf of Mexico towards the end of the week.  This trough will be weak compared to the parent trough over the northern Plains, yet there should still be an influence strong enough to develop a southwesterly steering current.  As a result, I think what we’ll see is that as we move towards the end of the week, Cuba will be significantly impacted by Gustav.  Depending on how much land Gustav moves over, the circulation may be significantly disrupted.  However, once Gustav moves into the Gulf of Mexico, Gustav will have the potential to redevelop, intensify, and impact somewhere between Louisiana and the eastern Florida coast.  Where exactly, I’m not sure, but I think these locations will be under a threat by next weekend.