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| #1009456 (Received by flhurricane at: 5:03 PM 24.Jul.2020) TCDAT3 Tropical Storm Hanna Discussion Number 8 NWS National Hurricane Center Miami FL AL082020 400 PM CDT Fri Jul 24 2020 Satellite imagery, along with Doppler radar data from Houston and Corpus Christi, indicate that Hanna has been getting better organized over the past several hours. Curved banding features have improved and a banding eye has developed in the radar data. The NOAA reconnaissance aircraft reported SFMR winds of 43-45 kt on its last outbound leg and a ship D5DE5 just east of the center reported an elevated wind speed of 51 kt at 1400Z. Based on these data, along with an estimated pressure of 999 mb from surrounding oil rigs, the initial intensity has been conservatively increased to 45 kt. Reconnaissance and radar fix data indicate that Hanna has turned westward, and the motion is now 275/09 kt. Hanna is forecast to move generally westward along the southern periphery of a deep-layer ridge for the next 24 hours, with landfall expected along the south-central coast of Texas within the hurricane warning area Saturday afternoon or early evening. The new NHC forecast track is just an extension of the previous advisory track, and lies close to an average of the consensus models TVCN, NOAA-HCCA, and FSSE. Given the improved internal structure noted in radar imagery, along with SSTs of at least 30 deg C and an impressive outflow pattern, increased frictional convergence as the cyclone moves closer to the coast and the approaching nocturnal convective maximum should support additional strengthening, and Hanna is now forecast to become a hurricane prior to making landfall. The NHC forecast of 65 kt in 24 hours is between the latest HWRF model run, which brings Hanna to 70 kt just prior to landfall, and the intensity consensus models HCCA and IVCN, which are just below hurricane strength. Due to Hanna forecast to reach hurricane strength, Hurricane and Storm Surge Warnings have been issued for portions of the Texas coast. Key Messages 1. There is a danger of life-threatening storm surge along the Texas coast from Baffin Bay to Sargent, where a Storm Surge Warning is in effect. Residents in these locations should follow advice given by local emergency officials. 2. Hurricane conditions are expected along the Texas coast from Baffin Bay to Mesquite Bay, where a Hurricane Warning is in effect. Tropical storm conditions are expected to first reach the coast within the warning area Saturday morning. 3. Hanna is expected to produce heavy rains across portions of southern Texas and northeastern Mexico. These rains could result in life-threatening flash flooding and isolated minor to moderate river flooding. FORECAST POSITIONS AND MAX WINDS INIT 24/2100Z 27.3N 94.3W 45 KT 50 MPH 12H 25/0600Z 27.4N 95.6W 55 KT 65 MPH 24H 25/1800Z 27.3N 97.2W 65 KT 75 MPH 36H 26/0600Z 27.0N 98.6W 40 KT 45 MPH...INLAND 48H 26/1800Z 26.6N 100.3W 25 KT 30 MPH...INLAND 60H 27/0600Z 25.6N 102.0W 20 KT 25 MPH...INLAND 72H 27/1800Z...DISSIPATED $$ Forecaster Stewart |