Forecast for 99L still uncertain
Since 99L has not yet formed a well-defined circulation center, it has been difficult for models to agree on its future track and intensity. This situation will likely continue until at least Thursday afternoon, when the SHIPS model predicts that wind shear will fall to the moderate range, 10 - 20 knots. This drop in shear will potentially allow 99L to organize into a tropical storm and give the models something more substantial to chew on.

A strong upper-level ridge now covering much of the Southeast U.S. and northern Gulf of Mexico will remain in place through the weekend, which should keep 99L on its general west-northwest track through at least Friday. Two of our three reliable models for predicting tropical genesis, the ECMWF and UKMET, continued to show development of 99L into a tropical storm by Friday in their latest 12Z Wednesday runs. These models brought 99L across or near South Florida on Sunday and into the Gulf of Mexico, with a second landfall occurring on the Florida Gulf Coast on Tuesday. Our other reliable tropical cyclone genesis model, the GFS, continued to insist that 99L would not develop through Sunday. In their 2 pm EDT Wednesday Tropical Weather Outlook, NHC gave 99L 2-day and 5-day development odds of 60% and 80%, respectively.
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