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#1012356 (Received by flhurricane at: 10:51 AM 15.Aug.2020) TCDAT1 Tropical Storm Josephine Discussion Number 16 NWS National Hurricane Center Miami FL AL112020 1100 AM AST Sat Aug 15 2020 Josephine has a sheared cloud pattern in satellite imagery this morning, with the low-level center located near the western edge of the main convective area. An Air Force Reserve Hurricane Hunter aircraft investigating the storm reported flight-level winds as high as 47 kt at 925 mb, along with surface wind estimates from the Stepped Frequency Microwave Radiometer of 35-40 kt. Based on these data, the initial intensity remains 40 kt. The aircraft also reported that, while the area of westerly winds south of the center was small, the circulation is still closed and that the central pressure was near 1008 mb. The storm has moved a little to the left since the last advisory, with the motion now west-northwestward or 290/14 kt. Other than that, there is little change in the forecast track or the forecast track philosophy. During the next 2-3 days, Josephine or its remnants are likely to continue to move west-northwestward to the south and southwest of a subtropical high pressure area. After that, the system is forecast to re-curve to the north and north-northeast through a break in the western portion of the high. The new NHC forecast lies to the the center of the tightly- clustered guidance and near the various consensus models. Josephine is expected to remain in an environment of moderate to strong westerly shear for at least the next 48-60 h. This should cause the system to weaken, with the new intensity forecast now calling for Josephine to weaken to a depression between 36-48 h and degenerate to a remnant low by 72 h. Several global models forecast the cyclone to degenerate to a tropical wave before 72 h, and this remains a viable alternative forecast scenario, especially considering how small the closed circulation is. There is a chance that Josephine or its remnants could encounter a less hostile environment after 72 h. However, it is unclear at this time whether there will be enough left of the system to take advantage of that. KEY MESSAGES: 1. Josephine should pass far enough to the northeast of the Leeward Islands today and tonight to prevent major impacts. However, interests there should continue to monitor its progress until the storm has passed north of that area. 2. Locally heavy rainfall is possible in the northern Leeward Islands, the Virgin Islands, and Puerto Rico as Josephine passes by to the northeast. Isolated minor flooding is possible in Puerto Rico through Monday. FORECAST POSITIONS AND MAX WINDS INIT 15/1500Z 19.1N 60.2W 40 KT 45 MPH 12H 16/0000Z 19.8N 61.9W 40 KT 45 MPH 24H 16/1200Z 21.0N 64.1W 35 KT 40 MPH 36H 17/0000Z 22.3N 66.3W 35 KT 40 MPH 48H 17/1200Z 23.8N 67.9W 30 KT 35 MPH 60H 18/0000Z 25.2N 68.7W 30 KT 35 MPH 72H 18/1200Z 26.7N 69.1W 25 KT 30 MPH 96H 19/1200Z 29.0N 68.0W 25 KT 30 MPH...POST-TROP/REMNT LOW 120H 20/1200Z 32.5N 64.5W 20 KT 25 MPH...POST-TROP/REMNT LOW $$ Forecaster Beven |