000 WTNT44 KNHC 231454 TCDAT4 Tropical Depression Nine Discussion Number 2 NWS National Hurricane Center Miami FL AL092022 1100 AM EDT Fri Sep 23 2022 The depression remains highly sheared this morning. Visible satellite imagery and data from an Air Force Reserve Hurricane Hunter aircraft indicate the center of the system is still exposed to the east of the associated deep convection. The center also appears a bit elongated, with a couple of low-level swirls evident in satellite imagery that appear to be rotating around a mean center. The aircraft winds and a blend of the latest satellite estimates support an initial intensity of 30 kt for this advisory. The long-term motion of the depression is still west-northwestward at 12 kt. The cyclone is expected to move more westward over the next 24-36 h as a narrow low- to mid-level ridge builds to the north of the system. Then, an amplifying deep-layer trough over the eastern U.S. is forecast to weaken the ridge beginning on Sunday, which should cause the cyclone to turn northwestward and northward as it approaches western Cuba early next week. There is increased spread in the guidance for this portion of the track forecast, with day 5 positions that span from the eastern Gulf to east of the Florida peninsula. The latest NHC track forecast lies near the center of the guidance envelope and closely follows the IVCN and HCCA aids. This prediction is very similar to the previous one, with only slight westward adjustments at days 3-5 to reflect the latest model consensus trends. The moderate to strong deep-layer northeasterly shear over the cyclone is expected to persist through tonight, so only slight strengthening is forecast through early Saturday. But once the shear decreases to less than 10 kt this weekend, more significant intensification is forecast as the cyclone moves over SSTs in excess of 30 deg C. The latest NHC intensity forecast has been increased from the previous one and explicitly calls for rapid intensification as the cyclone crosses the northwestern Caribbean Sea. The system is forecast to approach the Cayman Islands and Cuba as a strengthening hurricane, with additional intensification likely once it emerges over the warm waters of the southeastern Gulf of Mexico. In fact, this forecast calls for the system to approach the Florida peninsula as a major hurricane by day 5, which is supported by the latest IVCN and HCCA aids. Key Messages: 1. The depression is expected to produce heavy rainfall and instances of flash flooding and possible mudslides in areas of higher terrain in Aruba, Bonaire, and Curacao. Heavy rains are also likely to spread into Jamaica, the Cayman Islands, and Cuba in the coming days. 2. The depression is expected to approach Jamaica as a tropical storm on Sunday and the Cayman islands as a hurricane on Monday. Watches for these locations may be required later today or on Saturday. 3. Early next week the system is forecast to move near or over western Cuba as a strengthening hurricane and then approach the Florida peninsula at or near major hurricane strength, with the potential for significant impacts from storm surge, hurricane-force winds, and heavy rainfall. While it is too soon to determine the exact magnitude and location of these impacts, residents in Cuba, the Florida Keys, and the Florida peninsula should ensure they have their hurricane plan in place and closely monitor forecast updates through the weekend. FORECAST POSITIONS AND MAX WINDS INIT 23/1500Z 14.2N 70.1W 30 KT 35 MPH 12H 24/0000Z 14.5N 71.7W 35 KT 40 MPH 24H 24/1200Z 14.7N 74.1W 35 KT 40 MPH 36H 25/0000Z 15.1N 76.3W 40 KT 45 MPH 48H 25/1200Z 16.1N 78.3W 45 KT 50 MPH 60H 26/0000Z 17.8N 79.9W 60 KT 70 MPH 72H 26/1200Z 19.8N 81.4W 75 KT 85 MPH 96H 27/1200Z 23.5N 82.8W 90 KT 105 MPH 120H 28/1200Z 26.7N 82.1W 100 KT 115 MPH $$ Forecaster Reinhart