Another Bahamas Blob to watch

An area of disturbed weather over the Bahama Islands is associated with an upper-level low pressure system. This low is kicking up some strong thunderstorms just east of Florida, and is expected to drift west over Florida by Thursday. The low is cold-cored, but is making the slow transition to a warm-cored system. It needs to have a warm core in order to develop into a tropical storm, and this process typically takes three or more days. Wind shear in the area is marginaly favorable for tropical cyclone formation today, 10 - 20 knots. This shear is forecast to decrease over the next day. There is an area of dry air over Florida for the system to contend with, and development will be hindered if its circulation center moves over the Florida Peninsula as expected Thursday. However, by Friday or Saturday, several computer models are indicating the possibility that the center will move back over the water east of Florida or Georgia, and a tropical cyclone will develop. Any storm that does develop is likely to get whisked quickly northwards or northeastwards by a strong trough of low pressure expected to move off the East Coast this weekend. People planning on spending the weekend on the Outer Banks of North Carolina should keep a careful eye on this system--the situtation is very similar to what we had at the end of June, when we almost had Tropical Storm Beryl hitting eastern North Carolina.


Figure 1. Current satellite image of the blob of disturbed weather over the Bahamas.

The rest of the tropical Atlantic is quiet today.

Jeff Masters