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ZCZC MIATCDAT4 ALL TTAA00 KNHC DDHHMM Hurricane Lee Discussion Number 45 NWS National Hurricane Center Miami FL AL142017 500 AM AST Fri Sep 29 2017 Lee's low-level center is partially exposed along the northern edge of the convective canopy due to almost 40 kt of northerly shear. ASCAT data from last evening showed winds as high as 70 kt, so assuming some weakening due to the belligerent shear, the initial intensity is lowered to 65 kt. Lee will be crossing the tight SST gradient to the north of the Gulf Stream within the next 6-12 hours, and along with continued strong shear, this should cause the cyclone to weaken further and become a tropical storm later today. Global model guidance then indicates that Lee will dissipate in the fast flow ahead of an approaching cold front by 36 hours. Even after Lee's circulation opens up, a swath of strong winds will likely continue eastward toward Ireland and the United Kingdom by days 2 and 3. Lee is accelerating northeastward with an initial motion of 040/22 kt. The cyclone should maintain that heading with its speed increasing further up until the time it dissipates. The track guidance is tightly clustered for the next 24 hours before dissipation, and the NHC forecast is mainly an update of the previous one. FORECAST POSITIONS AND MAX WINDS INIT 29/0900Z 38.3N 52.4W 65 KT 75 MPH 12H 29/1800Z 41.1N 48.0W 60 KT 70 MPH 24H 30/0600Z 45.4N 39.3W 50 KT 60 MPH 36H 30/1800Z...DISSIPATED $$ Forecaster Berg NNNN