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| #1017555 (Received by flhurricane at: 4:38 AM 18.Sep.2020) TCDAT5 Hurricane Teddy Discussion Number 24 NWS National Hurricane Center Miami FL AL202020 500 AM AST Fri Sep 18 2020 Teddy remains a powerful category 4 hurricane with a well-defined eye and intense eyewall. There have been occasional dry slots that have eroded some of the convection in the eyewall and rain bands, but these seem to be transient. The satellite intensity estimates currently range from 90 kt to 128 kt, and based on a blend of that data, the initial intensity is set at 115 kt for this advisory. The hurricane is moving northwestward at 11 kt. Teddy is expected to continue moving northwestward at about the same forward speed during the next couple of days as it moves on the southwestern periphery of a subtropical high pressure system. By the end of the weekend, when Teddy will likely be approaching Bermuda, a turn to the north or north-northeast is forecast to occur as a mid- to upper-level trough moves closer to the system. However, the trough is expected to cut off, causing Teddy to turn slightly to the left early next week and approach Atlantic Canada in 4 to 5 days. The models are in fairly good agreement, and only small changes were made to the previous NHC track prediction. The major hurricane will likely maintain its intensity, or fluctuate in strength, during the next day or so while it remains in generally favorable conditions of low wind shear, warm waters, and a fairly moist air mass. However, the intensity models all show a slow weakening trend after that likely due to Teddy tracking over the cool SST wake left behind from Paulette and an increase in shear by early next week. Teddy is now forecast to transition to a powerful extratropical cyclone by the end of the forecast period based on the global model guidance. The NHC intensity forecast lies near the high end of the guidance envelope, in best agreement with the LGEM dynamical-statistical model. Teddy is producing a large area of high seas. The maximum seas estimated by TAFB near the core of the hurricane are around 40 feet. Swells from Teddy are spreading far from the center, see Key Messages below. Key Messages: 1. Teddy is expected to approach Bermuda as a hurricane this weekend and make its closest approach to the island late Sunday or Monday. While the exact details of Teddy`s track and intensity near the island are not yet known, the risk of strong winds, storm surge, and heavy rainfall on Bermuda is increasing. 2. Large swells produced by Teddy are expected to affect portions of the Leeward Islands, the Greater Antilles, the Bahamas, Bermuda, and the southeastern United States during the next few days. These swells could cause life-threatening surf and rip current conditions. FORECAST POSITIONS AND MAX WINDS INIT 18/0900Z 21.6N 55.4W 115 KT 130 MPH 12H 18/1800Z 22.8N 56.5W 120 KT 140 MPH 24H 19/0600Z 24.7N 58.1W 115 KT 130 MPH 36H 19/1800Z 26.6N 59.9W 110 KT 125 MPH 48H 20/0600Z 28.2N 61.6W 105 KT 120 MPH 60H 20/1800Z 29.8N 62.7W 100 KT 115 MPH 72H 21/0600Z 32.2N 62.8W 95 KT 110 MPH 96H 22/0600Z 39.7N 61.9W 90 KT 105 MPH 120H 23/0600Z 46.0N 62.9W 65 KT 75 MPH...POST-TROP/EXTRATROP $$ Forecaster Cangialosi |