The old frontal boundary that spawned the distubance off the East Coast we're watching has spawned a new disturbance over the Gulf of Mexico this afternoon. A large blow-up of intense thunderstorms south of New Orleans marks the center of this disturbance. With wind shear only 5-10 knots, this region is probably the bigger threat to develop than its sister east of Florida, which is under higher wind shear. Developments from old fronts are usually slow, and I expect Thursday is the earliest we would have to worry about a tropical depression forming. Steering currents are weak, but a slow motion to the south or southwest away from Louisiana should begin tonight. The NHC has not run their package of preliminary model runs on this system yet, but I will post them as soon as they do.East coast of Florida disturbance
Heavy thunderstorms continue over the waters east of Florida this evening along a broad area of low pressure that has developed from the remains of an old cold front. Wind shear
is 10-15 knots in a narrow band along this old front, which is low enough to allow some development to occur. This disturbance remains poorly organized, with only a moderate amount of heavy thunderstorm activity. The Hurricane Hunter mission scheduled for today was canceled and rescheduled for Wednesday.
The computer models are forecasting that any system that forms in this area will begin moving northwestwards towards the Carolinas over the next two days, in response to a trough of low pressure swinging across the eastern U.S. When the trough moves out to sea on Thursday, high pressure is forecast to build back in, forcing the system back towards the west, or leaving it nearly stationary off the East Coast. None of the computer models forecast that the storm will grow to anything stronger than a 40-mph tropical storm.Figure 1.
Current satellite of the Gulf of Mexico.Figure 2.
Preliminary models tracks for the East Coast disturbance.
I'll be back Wednesday with my Atlantic tropical outlook for the rest of August.