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#937962 (Received by flhurricane at: 10:50 PM 31.Aug.2018) TCDAT1 Tropical Depression Six Discussion Number 7 NWS National Hurricane Center Miami FL AL062018 1100 PM AST Fri Aug 31 2018 Convection associated with the depression is becoming more concentrated, although the center still appears to be near the eastern edge of the convective mass. The latest satellite intensity estimates from TAFB and SAB are 30 and 25 kt repsectively, while the CIMSS satellite consensus method suggests the cyclone has become a tropical storm. Based on the available data, the initial intensity remains a possibly conservative 30 kt. The depression is feeling the effects of moderate easterly vertical wind shear, with little or no cirrus outflow in the eastern semicircle. The initial motion is now 285/12. Deep layer easterly or east- southeasterly flow on the south side of the subtropical ridge should steer the cyclone generally west-northwestward across the open Atlantic ocean for the next 3-4 days. After that time, the cyclone is expected to turn northwestward toward a weakness in the subtropical ridge. The track guidance remains in good agreement with this scenario, although there remains some spread on how sharp the turn will be near the end of the forecast period. The new forecast track, which is an update of the previous forecast, is near the various consensus models. While the current shear is expected to subside during the next day or so, the forecast track takes the cyclone over waters that cool to near 26C in about 48 h. The intensity forecast thus calls for only gradual intensification through this time. After 48-72 h, the system should move over warmer water, but also should encounter increasing westerly shear. The intensity guidance responds to this combination of ingredients by showing little change in strength. The new intensity forecast, which is unchanged from the previous forecast, is in the stronger portion of the inetnsity guidance and above the forecasts of the consensus models. FORECAST POSITIONS AND MAX WINDS INIT 01/0300Z 14.2N 25.5W 30 KT 35 MPH 12H 01/1200Z 14.7N 27.4W 35 KT 40 MPH 24H 02/0000Z 15.5N 29.9W 40 KT 45 MPH 36H 02/1200Z 16.3N 32.6W 45 KT 50 MPH 48H 03/0000Z 17.0N 35.2W 50 KT 60 MPH 72H 04/0000Z 18.5N 40.0W 55 KT 65 MPH 96H 05/0000Z 20.5N 44.5W 60 KT 70 MPH 120H 06/0000Z 23.0N 47.5W 55 KT 65 MPH $$ Forecaster Beven |