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| #1009340 (Received by flhurricane at: 11:03 PM 23.Jul.2020) TCDAT3 Tropical Storm Hanna Discussion Number 5 NWS National Hurricane Center Miami FL AL082020 1000 PM CDT Thu Jul 23 2020 The system continues to organize with curved bands becoming better established around the center. The cyclone certainly has the appearance of a tropical storm, and just minutes ago the NOAA Hurricane Hunters found winds to support upgrading the system to a 35-kt tropical storm. Data from the aircraft also show that the minimum pressure has dropped to 1002 mb, indicating that the system is on a developing trend. Hanna is moving fairly slowly to the west-northwest, with the latest initial motion estimated to be 285/6 kt. This west-northwest motion should continue on Friday, but a turn to the west is expected by Friday night as a subtropical ridge strengthens to the north of the cyclone. This steering flow should take the center of the storm across the southern Texas coast in 36 to 48 hours. After landfall, the storm is forecast to turn south of west across extreme southern Texas and northern Mexico. The models have shifted southward again this cycle, and the NHC track forecast has been adjusted in that direction. Additional strengthening seems quite likely until the storm makes landfall since it is expected to remain over the very warm Gulf of Mexico waters and in generally low wind shear conditions. After landfall, steady weakening should commence, and the cyclone should dissipate over the rugged terrain of northern Mexico in about 4 days. The NHC intensity forecast is a little above the previous one and at the high end of the guidance given the system`s well organized structure and favorable environment. Due to the southward shift in the track forecast, the tropical storm warning has been extended southward from Port Mansfield to the Mouth of the Rio Grande. Tropical Storm Hanna is the earliest 8th storm on record. The previous record was in 2005 when Harvey formed on August 3rd. Key Messages 1. Hanna is forecast to strengthen and it is expected to bring tropical-storm-force winds to portions of the Texas coast, where a tropical storm warning is in effect. 2. Hanna is expected to produce heavy rains across portions of Louisiana, southern Texas, and northern Mexico. These rains could result in flash flooding and isolated minor-to-moderate river flooding. FORECAST POSITIONS AND MAX WINDS INIT 24/0300Z 26.2N 91.4W 35 KT 40 MPH 12H 24/1200Z 26.6N 92.8W 40 KT 45 MPH 24H 25/0000Z 27.1N 94.5W 45 KT 50 MPH 36H 25/1200Z 27.2N 96.3W 55 KT 65 MPH 48H 26/0000Z 27.2N 97.8W 45 KT 50 MPH...INLAND 60H 26/1200Z 27.0N 99.3W 30 KT 35 MPH...INLAND 72H 27/0000Z 26.5N 100.5W 25 KT 30 MPH...INLAND 96H 28/0000Z...DISSIPATED $$ Forecaster Cangialosi |