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#1143805 (Received by flhurricane at: 5:00 PM 15.Jul.2023) TCDAT5 Subtropical Storm Don Discussion Number 7 NWS National Hurricane Center Miami FL AL052023 500 PM AST Sat Jul 15 2023 Don has a poor appearance on the latest satellite imagery, with only weak banding noted on the southeastern side of the circulation, mostly removed from the center, and only moderate convection. With the overall degradation in the satellite presentation, the current wind speed is lowered slightly to 35 kt, consistent with the latest TAFB classification. The environment near Don is pretty harsh during the next few days, with waters of 23-24C, dry air aloft, and bouts of shear. While this should be counteracted by cool upper-level conditions, which promote deep convection over lower sea-surface temperatures than typical, most factors suggest some weakening next week. Thus the latest forecast of Don is decreased from the previous one, leaning closer to the global model solutions that generally show the system becoming a depression in a day or so. While there`s a chance of re-strengthening at long range, it is probably just as likely that the system will degenerate into a remnant low before that point. Don continues wobbling, but appears to have started its northward motion at about 8 kt. The storm should turn eastward by late tomorrow and southward on Tuesday while it moves around the northern periphery of a strong subtropical ridge. Don will probably enter a weaker steering flow near midweek, with little net motion expected for a day or so. Only minor eastward adjustments were required to the NHC track forecast at long range as much of the guidance come in close to the previous prediction. For such an unusual July track, the guidance is in fairly good agreement, and the NHC track is just west of the model consensus by day 5. FORECAST POSITIONS AND MAX WINDS INIT 15/2100Z 37.3N 48.6W 35 KT 40 MPH 12H 16/0600Z 38.3N 48.5W 35 KT 40 MPH 24H 16/1800Z 39.3N 47.3W 30 KT 35 MPH 36H 17/0600Z 39.4N 45.3W 30 KT 35 MPH 48H 17/1800Z 38.6N 43.1W 30 KT 35 MPH 60H 18/0600Z 37.1N 41.5W 30 KT 35 MPH 72H 18/1800Z 35.4N 40.7W 30 KT 35 MPH 96H 19/1800Z 33.2N 41.0W 35 KT 40 MPH 120H 20/1800Z 33.5N 42.0W 35 KT 40 MPH $$ Forecaster Blake |