ZCZC MIATCDEP2 ALL TTAA00 KNHC DDHHMM Hurricane Gilma Discussion Number 37 NWS National Hurricane Center Miami FL EP072024 1100 PM HST Mon Aug 26 2024 Satellite imagery depicts Gilma has started to weaken, and become less organized over the last several hours. Infrared images indicate that the previous well-defined eye has filled, and cloud tops have started to warm. The system is starting to encounter some westerly wind shear as well, as evident by a sharper sheared edge on the western side of the cyclone. A SSMIS microwave pass around 03Z depicts the eyewall has started to become less pronounced on the southern side, and may even be open. Subjective and objective intensity estimates have decreased from the previous advisory and range between 85-95 kt. Given the satellite degradation and a blend of the intensity estimates, the initial intensity is lowered to 90 kt for this advisory. Gilma is moving westward at 275/9 kt. A subtropical ridge should continue to steer the system generally westward to west-northwestward, with a gradual increase in forward speed over the next several days. On this track, Gilma should enter the Central Pacific basin by tomorrow. The track guidance continues to be fairly well clustered, with the main difference being the forward speed. The NHC track forecast is a little faster than the previous one, and lies near the simple consensus aids. While Gilma has fought off the marginal environment and maintained hurricane status longer than anticipated, it seems the atmospheric and oceanic conditions are becoming increasingly unfavorable. Westerly wind shear is starting to increase, as is evident in the satellite depiction, and is forecast to increase throughout the next several days. The system is also starting to move into a drier and more stable airmass with sub 26C sea-surface temperatures. This will result in steady weakening throughout the forecast period. Model simulated satellite suggest that Gilma will struggle to produce deep convection around 72 h and is now forecast to degenerate into a remnant low at that time. Global models also indicate that Gilma should dissipate into an open trough by the end of the forecast period. The NHC intensity forecast is similar to the previous and lies near the simple and corrected consensus intensity aids. FORECAST POSITIONS AND MAX WINDS INIT 27/0900Z 18.5N 139.2W 90 KT 105 MPH 12H 27/1800Z 18.6N 140.9W 75 KT 85 MPH 24H 28/0600Z 18.8N 143.2W 60 KT 70 MPH 36H 28/1800Z 19.2N 145.5W 50 KT 60 MPH 48H 29/0600Z 19.8N 147.8W 45 KT 50 MPH 60H 29/1800Z 20.2N 150.0W 40 KT 45 MPH 72H 30/0600Z 20.7N 152.3W 35 KT 40 MPH...POST-TROP/REMNT LOW 96H 31/0600Z 21.8N 156.6W 30 KT 35 MPH...POST-TROP/REMNT LOW 120H 01/0600Z...DISSIPATED $$ Forecaster Kelly NNNN