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| #1012066 (Received by flhurricane at: 10:39 PM 12.Aug.2020) TCDAT1 Tropical Depression Eleven Discussion Number 6 NWS National Hurricane Center Miami FL AL112020 1100 PM AST Wed Aug 12 2020 Conventional satellite imagery and a fortuitous ASCAT-B scatterometer overpass indicate that the center of circulation is a little farther south than previously estimated and remains well to the southeast of the deep convective canopy. The latest UW-CIMSS shear analysis confirms modest east-southeasterly shear impinging on the cloud pattern. A compromise of the satellite intensity estimates from TAFB and SAB, and the aforementioned scatterometer pass retains the initial intensity at 30 kt. Large-scale models and the statistical-dynamical intensity guidance still show the shear abating soon which should result in gradual strengthening with a peak intensity of 50 kt in 2 days. After that time, the cyclone is forecast to encounter moderate to strong southwesterly shear associated with a deep-layer trough stretching over the southwestern Atlantic. This change in the upper wind pattern should induce steady weakening. A number of the global models indicate that the cyclone will become a remnant low by day 4 and open up into a trough by day 5 which is certainly possible. The NHC forecast is similar to the previous advisory but indicates a more expeditious weakening trend beyond the 48 hour period in deference to the global model solution. The initial motion is estimated to be westward, or 275/13 kt, within the low to mid-tropospheric easterly flow produced by a subtropical ridge anchored to the north of the depression. The song remains the same...there is virtually no change to the forecast philosophy and only a slight shift to the left of the previous track forecast was made in response to the southward initial position adjustment. FORECAST POSITIONS AND MAX WINDS INIT 13/0300Z 12.5N 47.1W 30 KT 35 MPH 12H 13/1200Z 13.0N 48.4W 35 KT 40 MPH 24H 14/0000Z 14.2N 51.0W 40 KT 45 MPH 36H 14/1200Z 15.7N 53.7W 45 KT 50 MPH 48H 15/0000Z 17.0N 56.4W 50 KT 60 MPH 60H 15/1200Z 18.3N 58.9W 45 KT 50 MPH 72H 16/0000Z 19.7N 61.4W 40 KT 45 MPH 96H 17/0000Z 22.5N 65.6W 35 KT 40 MPH 120H 18/0000Z 25.6N 67.5W 30 KT 35 MPH $$ Forecaster Roberts |