Since this time yesterday, Isabel's MSLP has fallen and additional 18mb and sustained winds have increased by 15kts. After a brief period of shear and internal reorganization, she has now taken on the most classic of appearances, rivaling anything else in recent memory. The outflow channels are well-established, the eye is clear and hard-edged, and the eyewall forms a thick symmetric band of -75C cloud tops. As of 15Z today, Hurricane Isabel was located at 21.4N 54.5W and tracking W at 8kts. Intensity is 130kts and 930mb. The CAT5 transition occurs at 140kts and about 920mb, so she's just borderline, and with SSTs of 28.3C and increasing, it's not out of the realm of possibility over the next couple days to see the basin's first CAT5 hurricane since Mitch '98. Phil Klotzbach (CSU) reports the following: "As of the 15Z advisory today, we have already had 8.75 IHD this month which puts us in a tie for sixth place all-time with 1995. The maximum number of IHD for September is 15.75 set in 1961. Isabel alone could very likely put us at or very close to that record." NHC's 5-day track forecast places her just northeast of the Bahamas by Tuesday morning, and if she recurves into the US east coast, it would be about 7-8 days from today... just something to keep a close eye on as the days go by. If you wish to be astounded with high resolution (1km spatial and 1min temporal) visible satellite imagery from GOES-12, please visit http://www.cira.colostate.edu/ramm/rmsdsol/RSOMAIN.HTML and click on the GOES-EAST Visible Floater link.
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