Official Discussion issued by the National Hurricane Center
(AL012024) DATA RELEASED: 6/18/2024 10:00:00 AM UTC
Copy of official data Potential Tropical Cyclone One Discussion Number 4 NWS National Hurricane Center Miami FL AL012024 1000 AM CDT Tue Jun 18 2024 The disturbance's overall envelope is becoming slightly better defined, although there is still no evidence that a well-defined center of circulation has developed. Deep convection is increasing somewhat near the estimated center, but the most widespread activity is blossoming farther north over the northwestern Gulf of Mexico. The system is still being designated as a potential tropical cyclone with 35-kt winds, and an Air Force Reserve reconnaissance aircraft is currently surveying the system's wind field to assess its structure. The disturbance is moving generally northward, or 005/6 kt, although the centroid of the cloud pattern suggests it may have jogged east a bit. A continued slow motion is expected through tonight as the system gradually consolidates, but a turn toward the west with an increase in forward speed is forecast Wednesday and Wednesday night due to a mid-level ridge building southwestward over the southeastern United States. The updated NHC track forecast is similar to the previous one during the first 24 hours, but is then a bit faster after that, trending toward the HCCA and TVCA consensus aids. The system's broad nature will continue to inhibit significant strengthening despite otherwise conducive environmental conditions. Global model fields suggest the circulation will tighten up and develop a well-defined center on Wednesday while the system approaches the coast of Mexico. Intensification becomes more of a possibility at that point, and gradual strengthening is forecast on Wednesday while the system approaches the coast. It should be noted that regardless of the exact track of the low, we expect this system to have a large area of heavy rains, moderate coastal flooding and tropical-storm-force winds well north of the center. The official wind speed probabilities are likely underestimating the chances of tropical-storm-force winds along the Texas coast because of the unusually large and asymmetric area of strong winds on the northern side of the circulation. Key Messages: 1. Users are reminded not to focus on the exact forecast track of this system. The disturbance is very large with rainfall, coastal flooding, and wind impacts likely to occur far from the center along the coasts of Texas and northeastern Mexico. 2. Rainfall associated with Potential Tropical Cyclone One will impact large regions of Central America, north across northeastern Mexico and into South Texas. This rainfall will likely produce considerable flash and urban flooding along with new and renewed river flooding. Mudslides are also possible in areas of higher terrain across Central America into Northeast Mexico. 3. Moderate coastal flooding is likely along much of the Texas Coast beginning today and continuing through midweek. 4. Tropical storm conditions are expected to begin tonight or Wednesday along portions of the Texas coast south of Port OG��Connor and along portions of the coast of northeastern Mexico within the Tropical Storm Warning area. FORECAST POSITIONS AND MAX WINDS INIT 18/1500Z 21.8N 92.7W 35 KT 40 MPH...POTENTIAL TROP CYCLONE 12H 19/0000Z 22.5N 93.3W 35 KT 40 MPH...POTENTIAL TROP CYCLONE 24H 19/1200Z 23.0N 95.2W 40 KT 45 MPH...TROPICAL CYCLONE 36H 20/0000Z 23.3N 97.5W 45 KT 50 MPH...TROPICAL CYCLONE 48H 20/1200Z 23.3N 100.3W 30 KT 35 MPH...INLAND 60H 21/0000Z...DISSIPATED $$ Forecaster Berg |