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| #1016070 (Received by flhurricane at: 4:51 AM 11.Sep.2020) TCDAT2 Tropical Storm Paulette Discussion Number 18 NWS National Hurricane Center Miami FL AL172020 500 AM AST Fri Sep 11 2020 Paulette continues to experience the effects of 35-40 kt of southwesterly vertical shear, which has caused the center to occasionally become exposed to the south and southwest of the primary convective bursts. Since the various satellite intensity estimates are unchanged since the last scatterometer overpass, the initial intensity is held at 55 kt. However, this could be a little generous. The initial motion is west-northwestward or 300/9 kt. There is little change to either the forecast track philosophy or the forecast track from the last advisory. The track guidance models remain in good agreement between a generally northwest to west-northwestward motion over the next 3-4 days as the cyclone is steered by the subtropical ridge to its north and northeast. Around day 4, the cyclone is expected to recurve into the westerlies through a break in the ridge, with this turn to the northeast expected at about the time of closest approach to Bermuda. The new forecast track lies close to the various consensus models. It should be noted that there is still sufficient spread in the track guidance such that it is too soon to know what types of impacts Paulette could have on Bermuda early next week. The global models are in reasonable agreement that the shear over Paulette should subside, although it may be another 24 h before it subsides enough that significant strengthening can occur. After that, conditions should be favorable for strengthening until the system again encounters strong upper-level winds near 120 h after recurvature. The intensity guidance is in good agreement that Paulette will strengthen to a hurricane during this time and reach a peak intensity in about 96 h, and the new intensity forecast has only minor changes from the previous forecast. The new forecast is close to, but a little weaker than the various intensity consensus models. Key Messages: 1. Paulette is expected to approach Bermuda as a hurricane this weekend and make its closest approach to the island on Monday and Tuesday. While the exact details of Paulette`s track and intensity near the island are not yet known, the risk of strong winds, storm surge, and heavy rainfall on Bermuda continues to increase. 2. Swells produced by Paulette are expected to affect portions of the Leeward Islands, the Greater Antilles, the Bahamas, Bermuda, and the southeastern United States into the weekend. These swells could cause life-threatening surf and rip current conditions. FORECAST POSITIONS AND MAX WINDS INIT 11/0900Z 23.1N 51.7W 55 KT 65 MPH 12H 11/1800Z 23.9N 53.1W 55 KT 65 MPH 24H 12/0600Z 25.3N 54.9W 55 KT 65 MPH 36H 12/1800Z 26.8N 56.7W 60 KT 70 MPH 48H 13/0600Z 28.2N 58.8W 65 KT 75 MPH 60H 13/1800Z 29.5N 61.2W 75 KT 85 MPH 72H 14/0600Z 30.7N 63.3W 85 KT 100 MPH 96H 15/0600Z 33.5N 64.0W 90 KT 105 MPH 120H 16/0600Z 36.0N 59.5W 90 KT 105 MPH $$ Forecaster Beven |