|
Show Selection: |
| #1185033 (Received by flhurricane at: 8:48 PM 18.Jun.2024) TCDAT1 Potential Tropical Cyclone One Discussion Number 5 NWS National Hurricane Center Miami FL AL012024 400 PM CDT Tue Jun 18 2024 Air Force Reserve and scatterometer data show that the disturbance consists of a large northwest-to-southeast-oriented circulation with a 150-250-n mi wide area of light winds and a broad minimum in pressure. The scatterometer data also revealed that the strongest winds--30 to 35 kt--are located about 360 n mi north of the estimated center. With the continued lack of a well-defined center and little central convection, the system is still being designated as a potential tropical cyclone at this time. The system is moving generally northward, or 360/5 kt. A mid-level ridge over the eastern United States is forecast to build southwestward, forcing the disturbance to turn westward and accelerate toward the coast of Mexico tonight and on Wednesday. The model trackers appear to be too fast relative to the model fields themselves. As a result, the NHC official track forecast is slower than deterministic and consensus trackers, and brings the center of the system to the coast of Mexico in about 36 hours. This could still be a little fast since the global models have the center just offshore of Mexico at that time. Global model fields suggest that the circulation will gradually consolidate over the next 24 hours, and the center could be well defined enough by then to designate the system as a tropical cyclone. Even if that occurs, only modest intensification is forecast before the center reaches land due to the continued broad nature of the circulation. The most aggressive intensity models peak the intensity between 40-45 kt, and the NHC forecast is within that range. Regardless of the exact track of the low, this system will have a large area of heavy rains, moderate coastal flooding and tropical-storm-force winds well north of the center. Importantly, 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. Life-threatening flooding and mudslides are likely in areas of higher terrain across the Mexican states of Coahuila and Nuevo Leon, including the city of Monterrey. 3. Moderate coastal flooding is likely along much of the Texas Coast through midweek. 4. Tropical storm conditions are expected to begin tonight or Wednesday along portions of the Texas coast south of San Luis Pass and along portions of the coast of northeastern Mexico within the Tropical Storm Warning area. FORECAST POSITIONS AND MAX WINDS INIT 18/2100Z 22.1N 92.7W 35 KT 40 MPH...POTENTIAL TROP CYCLONE 12H 19/0600Z 22.7N 93.9W 35 KT 40 MPH...POTENTIAL TROP CYCLONE 24H 19/1800Z 23.0N 95.7W 40 KT 45 MPH...TROPICAL CYCLONE 36H 20/0600Z 23.3N 97.8W 40 KT 45 MPH...NEAR THE MEXICO COAST 48H 20/1800Z 23.3N 100.2W 30 KT 35 MPH...INLAND 60H 21/0600Z...DISSIPATED $$ Forecaster Berg |
