TS Arlene passed over the extreme western tip of Cuba early this morning and has now entered the Gulf of Mexico, still bearing down on the US coast. A Tropical Storm Warning has been issued for eastern LA over to St. Marks FL, and a Hurricane Watch has been issued for MS, AL, and the western FL panhandle.
The anticipated ridge to the north of the storm is indeed forming, and will steer Arlene slightly west of due north, and decrease the vertical wind shear as it does so. This is the reason for the Hurricane Watch... it is possible that Arlene could intensify more rapidly as the shear lets up. Currently, convection is still displaced to the east and north of the low-level center.
At 15Z today, it was located at 24.0N 84.9W and tracking N at 11kts. Intensity is 50kts and 1000mb. The forecast is for gradual strengthening, acceleration, and nudging to the NNW. Landfall is expected Saturday afternoon as a strong tropical storm or even minimal hurricane, and the most likely area to experience the worst conditions still appears to be the MS/AL coasts.
Please visit my tropical Atlantic headquarters.