I've analyzed the 500mb Upper Air Analysis with Plots and as many here have posted concern continues with whether Irene will turn north before becoming a real threat to FL or as some models continue to suggest a more westward track. This evening upper air data from Bermuda indicated a 10 meter increase to 594 decameters which continues to suggest the Bermuda subtropical ridge remains strong. A re-analyzing of the Mid-Continental "Texas" upper ridge continues to be entrenched over drought-stricken Texas. The east coast longwave trough lies between the two and is progressive however based on 20 meter height falls I've re-drawn the bottom of the trough to be across the northern FL where it ends near the upper ridge axis along 29N latitude. There remains a break in the ridge along a north-south axis near 27N 72W. NOAA9 extensively sampled the entire envelope ahead of Irene. The COL is centered once again near 27N 72W. It was noted on the 22/09Z NHC discussion that if Irene reaches major hurricane status and with such a large circulation that outflow entering the westerlies to the north will also aid in keeping the upper ridge to the east strong again suggesting a closer approach to FL. New data this evening suggests this remains plausible. Intensity forecasting is problematic but Irene will be a major hurricane soon.

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