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ZCZC MIATCDAT4 ALL TTAA00 KNHC DDHHMM Hurricane Lee Discussion Number 28 NWS National Hurricane Center Miami FL AL142017 1100 PM AST Sun Sep 24 2017 Lee has been relatively steady state in intensity during the last several hours. The 10 n mi eye of the hurricane remains distinct, and although the convective pattern around the eye is fairly symmetric, the cloud tops are not very cold. The latest Dvorak intensity estimates are 4.5/77 kt from both TAFB and SAB, and ADT values from CIMSS at the University of Wisconsin are slightly higher at 4.7/82 kt. Based on these data, the initial wind speed is held at 80 kt. Recent ASCAT data confirms that Lee is a very compact hurricane, with tropical-storm-force winds extending only 30 n mi from the center. Although wind shear is expected to remain low near Lee during the next couple of days, the hurricane is likely to be over its own cool SST wake for part of that time. These marginal SSTs and dry air will likely cause the system to change little in strength during the next couple of days. Thereafter, much drier air, a sharp increase in shear, and a track toward colder water should cause weakening by the end of the forecast period. The NHC intensity forecast is identical to the previous one and in best agreement with the consensus models IVCN and HCCA. Lee has been drifting east-southeastward during the past 12 hours in the flow on the south side of a mid- to upper-level trough. The trough is expected to bypass Lee on Monday, allowing high pressure to build to the north of the cyclone. This change in the steering pattern should cause the hurricane to turn westward by Monday night and Tuesday. By mid-week, another trough is expected to approach the hurricane, and this one should cause the system to accelerate to the northeast over the central Atlantic. The NHC track forecast has been adjusted to the west of the previous one to come into better agreement with the latest guidance. FORECAST POSITIONS AND MAX WINDS INIT 25/0300Z 31.1N 49.5W 80 KT 90 MPH 12H 25/1200Z 31.0N 49.4W 85 KT 100 MPH 24H 26/0000Z 30.7N 49.9W 85 KT 100 MPH 36H 26/1200Z 30.6N 51.2W 85 KT 100 MPH 48H 27/0000Z 30.8N 52.5W 80 KT 90 MPH 72H 28/0000Z 31.8N 54.1W 75 KT 85 MPH 96H 29/0000Z 34.7N 53.0W 70 KT 80 MPH 120H 30/0000Z 40.0N 46.5W 55 KT 65 MPH $$ Forecaster Cangialosi NNNN