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| #1063794 (Received by flhurricane at: 4:57 PM 29.Sep.2021) TCDAT5 Tropical Storm Victor Discussion Number 2 NWS National Hurricane Center Miami FL AL202021 800 PM CVT Wed Sep 29 2021 The cloud pattern continues to exhibit a large circulation with numerous curved bands surrounding the center. The strongest thunderstorms remain on the system`s west side. The latest Dvorak estimates from TAFB and SAB have both increased to 2.5/35 kt, and on that basis, the cyclone has been upgraded to a 35-kt tropical storm. Victor is still on a west-northwest course at about 11 kt. There has been little change to the track forecast reasoning. The cyclone is expected to continue west-northwestward during the next couple of days as it remains steered by the flow on the south side of a deep-layer ridge. By late Friday, however, the models show the western periphery of the ridge being eroded due to a mid- to upper-level low over the subtropical central Atlantic. As a result, the cyclone should turn northwestward by Friday night and then northward late this weekend or early next week. There remains a fair amount of spread in the timing and location of the northward turn with the GFS and HWRF still on the right side of the guidance envelope and the ECMWF showing the slowest and westernmost solution. Overall, the consensus models have not changed much and neither has the official track forecast. The storm is expected to remain in conducive environmental conditions for strengthening during the next couple of days. During that time period, Victor is forecast to move over 28-29 deg C waters while embedded within a moist airmass with very low wind shear (less than 10 kt). Rapid intensification sometimes occurs when conditions are this favorable, however, since the storm is broad and does not yet have an inner core, gradual strengthening seems more reasonable. The NHC forecast brings Victor to hurricane intensity in 36 hours. In a few days, however, the models show a pronounced increase in southwesterly shear and a notably drier atmosphere. These unfavorable conditions should end the opportunity for strengthening and promote a weakening trend. The NHC intensity forecast is similar to the previous one and remains near a blend of the HCCA, IVCN, and IVDR consensus models. FORECAST POSITIONS AND MAX WINDS INIT 29/2100Z 8.3N 25.5W 35 KT 40 MPH 12H 30/0600Z 8.8N 26.9W 45 KT 50 MPH 24H 30/1800Z 9.5N 28.9W 55 KT 65 MPH 36H 01/0600Z 10.3N 30.8W 65 KT 75 MPH 48H 01/1800Z 11.4N 32.4W 70 KT 80 MPH 60H 02/0600Z 12.8N 34.1W 70 KT 80 MPH 72H 02/1800Z 14.7N 35.8W 60 KT 70 MPH 96H 03/1800Z 19.3N 38.9W 50 KT 60 MPH 120H 04/1800Z 24.9N 40.9W 40 KT 45 MPH $$ Forecaster Cangialosi |