Tropical Cyclone Discussion
641 WTNT45 KNHC 311456 TCDAT5 Potential Tropical Cyclone Five Discussion Number 1 NWS National Hurricane Center Miami FL AL052026 1000 AM CDT Mon Aug 31 2026 The disturbance (AL97) that the NHC has been tracking over the northern Gulf of America continues to produce a small area of showers and thunderstorms with modest signs of organization. Overnight scatterometer data indicated the circulation lacked definition on the western side, and recent surface observations and data from the Air Force Hurricane Hunters suggest the center is still elongated and ill defined. However, given the expectation that the system will become a tropical cyclone, and the risk of tropical storm conditions for portions of the northwestern Gulf Coast, we are initiating advisories on Potential Tropical Cyclone Five. The initial intensity is set at a possibly generous 30 kt based on the overnight scatterometer data. The initial motion is uncertain given the system is still in its formative stage, but our best estimate is west-northwestward (285/4 kt). The track models agree that the system should continue west-northwestward during the next day or so and approach the Upper Texas and southwestern Louisiana coast within the warning area on Tuesday. The official NHC track forecast lies very near the HFIP corrected consensus (HCCA), near the center of the guidance envelope. A 48-h post-tropical forecast point is shown for continuity, but the system will likely be dissipated by that time. The small system is located over SSTs greater than 30 deg C, and the deep-layer shear appears fairly weak as diagnosed from the SHIPS guidance. Some strengthening is expected before the system reaches the coast on Tuesday, as long as it is able to develop a more cohesive tropical cyclone structure. Since the center is predicted to move onshore between 24-36 h, additional strengthening could occur between those forecast points that cannot be reflected in the official forecast. Given the anticipated small size of the system, it could be prone to quicker intensity changes, so additional strengthening beyond what is shown cannot be ruled out. The NHC intensity forecast lies at the top of the latest guidance. Key Messages: 1. Potential Tropical Cyclone Five is expected to bring tropical storm conditions to portions of the Upper Texas and southwestern Louisiana coasts on Tuesday. A Tropical Storm Warning is in effect from Port Bolivar, Texas, to the Vermilion/Cameron Parish Line, Louisiana. 2. Heavy rain will impact parts of the Upper Texas coast through east-central Texas into far southwestern Louisiana Tuesday and Wednesday as the system tracks inland. Flash flooding is likely across this region, especially in urban areas. 3. Minor to moderate coastal flooding is possible along the Upper Texas and southwestern Louisiana coasts. FORECAST POSITIONS AND MAX WINDS INIT 31/1500Z 27.8N 91.0W 30 KT 35 MPH...POTENTIAL TROP CYCLONE 12H 01/0000Z 28.3N 91.8W 35 KT 40 MPH...TROPICAL CYCLONE 24H 01/1200Z 29.1N 93.2W 40 KT 45 MPH 36H 02/0000Z 29.9N 94.4W 35 KT 40 MPH...INLAND 48H 02/1200Z 31.1N 95.5W 25 KT 30 MPH...POST-TROP/INLAND 60H 03/0000Z...DISSIPATED