000 WTNT42 KNHC 162048 TCDAT2 Potential Tropical Cyclone Twenty-Two Discussion Number 1 NWS National Hurricane Center Miami FL AL222023 400 PM EST Thu Nov 16 2023 NHC has been monitoring the development of a broad area of low pressure over the western Caribbean Sea during the past several days. Satellite images and recent data from an Air Force Reserve Hurricane Hunter aircraft indicate that the low has a closed but broad circulation, and there is no evidence yet of a well-defined center. Elongated bands of deep convection extend over much of the eastern part of the circulation and are streaming northward toward portions of the Greater Antilles. Since the system is forecast to become a tropical storm, and there is a risk of tropical-storm-force winds across portions of the Greater Antilles, southeastern Bahamas, and Turks and Caicos Islands during the next couple of days, advisories are being initiated on Potential Tropical Cyclone Twenty-Two. The initial motion is uncertain since the system does not yet have a well-defined center, but the overall cloud system appears to be moving generally north-northeastward, or 015/8 kt. The disturbance is forecast to turn northeastward by tonight due to a broad mid-level trough located over Florida and the adjacent waters. A continued northeastward motion with increasing forward speed is then expected through the weekend as the system becomes increasingly picked up by the trough. Although there is a bit uncertainty in the forecast track since there is not yet a center to track, the model guidance is in generally good agreement on this scenario. The NHC track forecast blends the latest TVCA and HCCA consensus aids. The system's broad nature, increasing southerly shear, and nearby dry air suggest that it likely won't strengthen much. That said, the disturbance could become a tropical depression or tropical storm tonight or on Friday if the circulation can contract enough for a well-defined center to form. Conditions should be sufficiently conducive to allow for modest strengthening, and the NHC intensity forecast is just below the IVCN and HCCA consensus aids. Most global model fields indicate the cyclone should become extratropical over the western Atlantic in about 3 days, and then become absorbed by a front by day 5. The most significant hazard from this system is likely to be heavy rainfall, especially in areas of higher terrain, across portions of Jamaica, southeastern Cuba, and Hispaniola. KEY MESSAGES: 1. Potential Tropical Cyclone Twenty-Two is forecast to become a tropical storm on Friday. Tropical storm conditions are possible across Jamaica, southeastern Cuba, Haiti, the southeastern Bahamas, and the Turks and Caicos Islands through Saturday, and tropical storm watches are now in effect for these areas. 2. Heavy rains will affect portions of Panama, Costa Rica, Jamaica, southeastern Cuba, and Hispaniola through Monday morning. This rainfall is likely to produce flash flooding, along with mudslides in areas of higher terrain. FORECAST POSITIONS AND MAX WINDS INIT 16/2100Z 15.2N 81.5W 30 KT 35 MPH...POTENTIAL TROP CYCLONE 12H 17/0600Z 15.7N 80.8W 30 KT 35 MPH...TROPICAL DEPRESSION 24H 17/1800Z 17.0N 79.0W 35 KT 40 MPH 36H 18/0600Z 19.2N 76.6W 40 KT 45 MPH 48H 18/1800Z 21.9N 73.3W 45 KT 50 MPH 60H 19/0600Z 25.3N 69.0W 45 KT 50 MPH 72H 19/1800Z 29.4N 64.5W 45 KT 50 MPH...POST-TROP/EXTRATROP 96H 20/1800Z 38.0N 54.1W 45 KT 50 MPH...POST-TROP/EXTRATROP 120H 21/1800Z...DISSIPATED $$ Forecaster Berg