Issued at 400 PM EST Mon Nov 04 2024
000 WTNT43 KNHC 042054 TCDAT3 Tropical Storm Rafael Discussion Number 5 NWS National Hurricane Center Miami FL AL182024 400 PM EST Mon Nov 04 2024 Deep convection continues to burst near the center of the system, with improving overall structure and curved banding depicted in recent satellite images. Recent Air Force Hurricane Hunter data has found flight level winds around 40-45 kt with higher SFMR values. The Hurricane Hunters also indicated that an eyewall appears to be developing. Based on the aircraft data, the intensity is being increased to 40 kt. The system is now designated as Tropical Storm Rafael, and is the seventeenth named storm of the Atlantic hurricane season. The storm has jogged a bit to the right of the previous track, and the initial motion is estimated 010/8 kt. A turn to the northwest is expected later tonight, and that motion is forecast to continue during the next few days as a ridge builds over the southwestern Atlantic and northeastern Caribbean. This motion should take the center of the system near Jamaica tonight, near or over the Cayman Islands by late Tuesday, and across western Cuba on Wednesday. After that time, when the system reaches the Gulf of Mexico, the model solutions diverge, which appears to be due to differences in the steering patterns and vertical depth of the storm. The NHC track forecast is largely an update of the previous one and remains close to the various consensus models. However, it should be noted that the track forecast over the Gulf of Mexico is of lower confidence. Given the improving overall structure with an inner core developing, combined with favorable environmental factors of low wind shear, high moisture, and warm SSTs all support intensification. Models all support steady to rapid intensification, and SHIPS RI probabilities indicate a near 40 percent chance of a 30 kt increase in the next 24 hours and a near 50 percent chance of a 55 kt increase in 48 hours. Thus, the latest NHC intensity forecast and peak intensity has been increased and lies near the higher end of the guidance envelope through the middle part of the forecast period. Based on the SHIPS RI guidance, future upward intensity adjustments during the first 48 h may be necessary in subsequent forecast cycles. In a few days, when the system reaches the central Gulf, a sharp increase in southwesterly vertical wind shear, drier air, and slightly cooler waters should end the strengthening trend and induce weakening, and the NHC intensity forecast follows these weakening trends and lies near the HCCA and IVCN consensus aids through the end of the forecast period. Key Messages: 1. Rafael is forecast to be a hurricane when it passes near or over the Cayman Islands by Tuesday evening where damaging hurricane-force winds, a dangerous storm surge, and destructive waves are expected. Tropical storm conditions are expected in Jamaica tonight and Tuesday. 2. Additional strengthening is forecast before Rafael reaches western Cuba and the Isle of Youth on Wednesday where there is an increasing risk of a dangerous storm surge and damaging hurricane-force winds. 3. Tropical storm conditions are possible in the Lower and Middle Florida Keys beginning late Wednesday or Wednesday night. 4. It is too soon to determine what, if any, impacts Rafael could bring to portions of the northern Gulf coast. Residents in this area should regularly monitor updates to the forecast. 5. Rafael will bring areas of heavy rain to portions of the western Caribbean, including Jamaica and Cuba through mid-week, where flooding and landslides are possible. Heavy rainfall will spread into Florida and adjacent areas of the Southeast United States mid to late week. FORECAST POSITIONS AND MAX WINDS INIT 04/2100Z 15.5N 76.7W 40 KT 45 MPH 12H 05/0600Z 16.8N 77.6W 55 KT 65 MPH 24H 05/1800Z 18.5N 79.1W 65 KT 75 MPH 36H 06/0600Z 20.2N 80.8W 75 KT 85 MPH 48H 06/1800Z 22.1N 82.4W 85 KT 100 MPH 60H 07/0600Z 23.6N 83.8W 80 KT 90 MPH 72H 07/1800Z 24.7N 85.0W 75 KT 85 MPH 96H 08/1800Z 26.0N 87.3W 65 KT 75 MPH 120H 09/1800Z 27.4N 89.4W 50 KT 60 MPH $$ Forecaster Kelly
