000 WTPZ42 KNHC 240232 TCDEP2 Hurricane Gilma Discussion Number 23 NWS National Hurricane Center Miami FL EP072024 500 PM HST Fri Aug 23 2024 Gilma's satellite depiction has changed very little since earlier today, as the eye has become filled and now the center resides beneath the central dense overcast (CDO) on both visible and infrared imagery. Deep convection continues to burst within the inner core with cold cloud tops to near -80 C, with generally good outflow in all directions. The subjective and objective intensity estimates have remained steady with this advisory as well, with a current intensity (CI) of 5.0 from both SAB and TAFB. Given the steady state of satellite imagery and the intensity estimates, the initial intensity is held at 90 kt for this advisory. The hurricane is continuing to move generally westward at an initial motion of 280/8 kt. A ridge has started to build to the north of Gilma, which will keep the system on a generally westward track, with a gradual increase in forward motion. The track model guidance is in fairly good agreement with the general direction the system moves, however how fast that increase in forward speed occurs leads to some along-track differences in the model suite, particularly at the end of the forecast period. The official NHC track forecast is near the previous forecast, just nudged slightly southward and faster, near the consensus aids. Gilma is in a low wind shear environment, however the system is about to run into cooler sea surface temperatures with very little ocean heat content beyond the next 24 h or so. As the system moves over cooler waters it will also encounter a much drier and stable airmass. These changes in oceanic and atmospheric conditions will lead to gradual weakening over the next 24 hours followed by an increasing rate of weakening through the end of the period. Towards the end of the forecast period, conditions continue to become unfavorable with upper-level westerly wind shear increasing, and the GFS depicts the system struggling to produce convection, becoming a remnant low at 120 h. The official NHC intensity forecast is similar to the previous advisory, near the simple consensus intensity aids. FORECAST POSITIONS AND MAX WINDS INIT 24/0300Z 17.5N 128.4W 90 KT 105 MPH 12H 24/1200Z 17.7N 129.7W 85 KT 100 MPH 24H 25/0000Z 18.0N 131.5W 80 KT 90 MPH 36H 25/1200Z 18.2N 133.4W 75 KT 85 MPH 48H 26/0000Z 18.4N 135.1W 70 KT 80 MPH 60H 26/1200Z 18.6N 137.0W 60 KT 70 MPH 72H 27/0000Z 18.9N 139.0W 50 KT 60 MPH 96H 28/0000Z 19.4N 143.7W 40 KT 45 MPH 120H 29/0000Z 20.3N 148.7W 30 KT 35 MPH...POST-TROP/REMNT LOW $$ Forecaster Kelly
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