By:
Dr. Jeff Masters,
12:24 PM GMT on September 26, 2009
Tropical Depression Eight formed last night near the coast of Africa, but is not destined to threaten land, and has only about a 50/50 chance of becoming Tropical Storm Grace. While wind shear is a moderate 10 - 20 knots, Sea Surface Temperatures (SSTs) are right at the threshold for tropical storm formation--26°C. There is only a small amount of dry air that is interfering with the storm, but the combination of cool SSTs and moderate wind shear will make TD 8 slow to organize. By Monday, shear is expected to reach a very high 25 - 30 knots, and this should tear the storm apart.
None of the computer models are forecasting tropical storm formation elsewhere in the Atlantic over the next seven days.
Figure 1. Current satellite image of Tropical Depression Eight.
Jeff Masters