ZCZC MIATCDAT2 ALL TTAA00 KNHC DDHHMM HURRICANE GASTON DISCUSSION NUMBER 40 NWS NATIONAL HURRICANE CENTER MIAMI FL AL072016 1100 AM AST THU SEP 01 2016 Despite a degraded satellite presentation, a 1302 UTC ASCAT-B pass over Gaston showed a large area of hurricane force winds southeast of the center and peak winds of 75 kt, and that will serve as the initial intensity for this advisory. Weakening is forecast as Gaston moves across the 26C SST isotherm later today and the vertical shear is expected to increase to 20-30 kt by 48 hours. Gaston should fall below hurricane strength tonight and gradually lose tropical characteristics by 48 hours. The low is forecast to dissipate by 72 hours, as shown in the global models. The NHC intensity forecast is close to the new IVCN intensity consensus aid. The hurricane is moving quickly east-northeastward, 070/21. Gaston will continue moving generally east-northeastward within the mid- latitude westerlies through dissipation. The new NHC forecast is near the middle of the guidance envelope and the multi-model consensus TVCN. Based on the current forecast, the Azores Meteorological Service has issued a Tropical Storm Warning for the islands of Faial, Pico, Graciosa, Sao Jorge, and Terceira in the central Azores. FORECAST POSITIONS AND MAX WINDS INIT 01/1500Z 37.6N 40.6W 75 KT 85 MPH 12H 02/0000Z 38.4N 37.1W 65 KT 75 MPH 24H 02/1200Z 39.1N 32.8W 55 KT 65 MPH 36H 03/0000Z 39.7N 29.8W 45 KT 50 MPH 48H 03/1200Z 41.0N 26.5W 35 KT 40 MPH...POST-TROPICAL 72H 04/1200Z...DISSIPATED $$ Forecaster Brennan NNNN