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| #1152737 (Received by flhurricane at: 10:47 PM 13.Sep.2023) TCDAT4 Hurricane Margot Discussion Number 27 NWS National Hurricane Center Miami FL AL142023 300 AM GMT Thu Sep 14 2023 Margot's satellite depiction has become more ragged during the last few hours. An earlier microwave pass showed that the center was partially opened on the northern and western sides of the system. Dry air is beginning to wrap into the center of the system, which has caused some of the banding features to become broken. The center has been cloud filled since the previous advisory, with overall warming cloud tops. Satellite Dvorak current intensity estimates were both 4.5 from TAFB and SAB. Given these estimates and the degraded satellite depiction, the initial intensity for this advisory is lowered to 75 kt. Margot continues to gradually slow down as it moves within the flow between a deep-layer ridge over the eastern Atlantic and an upper trough to its west. A general northward motion should continue over the next day or so. The steering pattern becomes fairly weak with a blocking ridge to the north of the system, causing Margot to meander over the north Atlantic and make a gradual clockwise loop over the next 2 to 3 days. There are still some large differences in the guidance envelope in the long term, but slightly better agreement than 24 h ago. By the end of the period, the storm will likely begin accelerating off to the east-northeast as it gets picked up by the westerlies, but the overall track forecast confidence remains low given the model spread. Margot's convective structure has degraded this evening. The system is entering a less favorable environment, with dry air entrainment beginning to erode some of the structure. Deep-layer shear is also forecast to increase, and upwelling of cooler waters due to the lack of forward motion should result in weakening of the system through the weekend. The NHC intensity forecast is similar to the previous advisory and lies near the corrected consensus aids, the HCCA and IVCN. Although the forecast keeps Margot a tropical cyclone through day 5, simulated satellite imagery from the global models suggests these increasingly hostile environmental factors could cause the system to lose organized convection and become post-tropical sooner. FORECAST POSITIONS AND MAX WINDS INIT 14/0300Z 35.2N 40.5W 75 KT 85 MPH 12H 14/1200Z 35.9N 40.2W 70 KT 80 MPH 24H 15/0000Z 36.4N 39.6W 65 KT 75 MPH 36H 15/1200Z 36.4N 39.3W 60 KT 70 MPH 48H 16/0000Z 36.1N 39.6W 55 KT 65 MPH 60H 16/1200Z 35.6N 40.5W 50 KT 60 MPH 72H 17/0000Z 35.5N 41.7W 45 KT 50 MPH 96H 18/0000Z 37.2N 43.2W 45 KT 50 MPH 120H 19/0000Z 40.4N 40.2W 45 KT 50 MPH $$ Forecaster Kelly |
