This morning, a ship near TD1 reported winds high enough to require upgrading TD1 to a Tropical Storm, the first of the season. Arlene is still over very warm SSTs, but the shear has not relaxed as much as expected and the low-level center is exposed to the southwest. This is still forecast to lessen in time as a ridge builds to the north of the storm. The ridge would put Arlene in a more friendly shear environment, and will also be responsible for steering it toward the AL/MS coast.
At 21Z today, TS Arlene was located at 20.2N 84.2W and tracking N at 7kts. Intensity estimated by satellite (a plane is en route) is 35kts and 1001mb. It should accelerate and gradually intensify, making landfall on Saturday evening as a strong TS.
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