Debby is having a hard time maintaining deep convection in the face of 25kt shear. The SST is 28C, but that warm water is quite shallow there too. It's located at 23.9N 43.3W and tracking NW at 15kts now, with a satellite-estimated intensity of 35kts and 1003mb... barely holding onto tropical storm status. The forecast is unchanged: fluctuate a bit in intensity and recurve by 55W.
At 21Z yesterday, the strong tropical wave near the Lesser Antilles was upgraded to TD5 based on an aircraft flight into it. Today at 21Z, it was further upgraded to TS Ernesto, again based on aircraft recon. The storm is experiencing decent westerly vertical wind shear, so the low-level center is displaced to the west from the deep convection. Recall that this wave was born in the Ethiopian Highlands way back on August 10 or so, and exited Africa on August 17.
At 19Z today, Ernesto was located at 14.1N 67.3W. The intensity is 40kts and 1004mb... this may be adjusted slightly for the official 21Z advisory.
The forecast for Ernesto is very interesting, particularly for the Gulf coast. Over the next couple of days, it is expected to maintain its WNW heading and somewhat formidable shear, but after that, it enters lower shear, and VERY high oceanic heat content in the western Caribbean. In 5 days, it should pass between Yucatan and Cuba, heading in to the Gulf of Mexico as a possibly powerful hurricane. There is too much uncertainly beyond 5 days, but once in the Gulf, it HAS to hit somewhere.
Elsewhere, a new potent tropical wave is introduced off the African coast around 18W with an embedded 1008mb Low. We're now entering the heart of the "Cape Verde season", so these all need to be watched closely.
Also, today is the 1-year anniversary of Hurricane Katrina's Florida landfall.
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