ZCZC MIATCDAT3 ALL TTAA00 KNHC DDHHMM Tropical Storm Leslie Discussion Number 40 NWS National Hurricane Center Miami FL AL132018 500 AM AST Sat Oct 06 2018 Leslie is producing a cluster of deep convection near its center of circulation and a far-reaching band that curls around the eastern side of the expansive circulation. The maximum winds are still estimated to be 50 kt based on last evening's ASCAT pass. Leslie's future intensity will largely be limited by a less-than-ideal thermodynamic environment, with the center moving over water temperatures of 24-25 degrees Celsius within its own cold wake during the next 48 hours. Some weakening is anticipated during that period, and the NHC forecast follows the intensity consensus and HCCA guidance. After 48 hours, some restrengthening is possible when Leslie reaches some warmer waters, although increasing westerly shear is likely to temper the amount of intensification. Leslie's current motion is northeastward, or 045/7 kt. The cyclone is becoming increasingly embedded within the mid-latitude westerlies, and these winds, with the assistance of a couple of shortwave troughs, are expected to push Leslie toward the east and southeast throughout the forecast period. The one notable model anomaly is the ECMWF, which shows Leslie becoming more separated from the mid-latitude flow and moving more slowly than shown in the other models on days 3 through 5. Even with that model being an outlier, the rest of the guidance has sped up a bit, pulling the consensus aids eastward. This resulted in the new NHC track forecast being a little faster than the previous one on days 4 and 5. Large swells generated by Leslie are expected to continue during the next few days across the eastern coast of the United States, Bermuda, the Bahamas, the Greater and Lesser Antilles, and Atlantic Canada. Please consult products from your local weather office as these conditions could cause life-threatening surf and rip currents. FORECAST POSITIONS AND MAX WINDS INIT 06/0900Z 37.2N 56.4W 50 KT 60 MPH 12H 06/1800Z 37.3N 55.0W 50 KT 60 MPH 24H 07/0600Z 37.1N 52.6W 50 KT 60 MPH 36H 07/1800Z 36.5N 50.2W 45 KT 50 MPH 48H 08/0600Z 35.7N 47.8W 40 KT 45 MPH 72H 09/0600Z 33.4N 42.6W 45 KT 50 MPH 96H 10/0600Z 30.5N 37.5W 50 KT 60 MPH 120H 11/0600Z 28.5N 32.5W 50 KT 60 MPH $$ Forecaster Berg