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| #1059746 (Received by flhurricane at: 10:39 PM 31.Aug.2021) TCDAT2 Tropical Depression Twelve Discussion Number 2 NWS National Hurricane Center Miami FL AL122021 200 AM CVT Wed Sep 01 2021 Satellite images indicate that the depression is gradually becoming better organized. An area of deep convection has been persisting near the center, and banding features are beginning to take shape. The latest Dvorak estimates from TAFB and SAB have increased to 2.5/35 kt, which would support upgrading the system to a tropical storm. However, a recent ASCAT-B overpass around 2300 UTC showed maximum winds in the 25-30 kt range in the northeastern quadrant, and based on that data the initial intensity is held at 30 kt. The tropical depression is moving fairly quickly to the west-northwest at 17 kt. The track forecast reasoning appears fairly straightforward. The cyclone is expected to move at a relatively fast pace to the west or west-northwest during the next couple of days as it remains on the south side of a strong mid-level ridge. After that time, a decrease in forward speed and a gradual turn to the northwest are expected as the system nears the southwestern side of the ridge. Although most of the models agree on the synoptic steering pattern, there is a fair amount of spread from days 3 to 5 in how soon the northwestward turn will occur. The NHC track forecast lies near the middle of the guidance envelope and is a little to the north of the previous one based on the more poleward initial position. Since the system is expected to be over relatively warm water and in an air mass of low wind shear and abundant moisture, steady strengthening is expected during the next couple of days. The depression is likely to become a tropical storm within the next 12 hours and a hurricane in 36 to 48 hours. Beyond a few days, an increase in shear and drier air should slow the rate of intensification. The NHC intensity forecast follows the trend of the HCCA, IVCN, and IVDR models. In addition, the global models all show the cyclone becoming fairly large toward the end of the forecast period. The NHC forecast wind radii is larger than the previous one, trending toward the radii consensus aid. FORECAST POSITIONS AND MAX WINDS INIT 01/0300Z 12.1N 23.2W 30 KT 35 MPH 12H 01/1200Z 12.6N 25.9W 40 KT 45 MPH 24H 02/0000Z 12.8N 29.2W 50 KT 60 MPH 36H 02/1200Z 13.2N 32.1W 60 KT 70 MPH 48H 03/0000Z 13.8N 35.1W 70 KT 80 MPH 60H 03/1200Z 14.5N 37.5W 80 KT 90 MPH 72H 04/0000Z 15.4N 40.1W 85 KT 100 MPH 96H 05/0000Z 18.0N 44.5W 90 KT 105 MPH 120H 06/0000Z 20.7N 47.9W 95 KT 110 MPH $$ Forecaster Cangialosi |