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| #1068622 (Received by flhurricane at: 10:50 AM 05.Nov.2021) TCDAT1 Tropical Storm Wanda Discussion Number 23 NWS National Hurricane Center Miami FL AL212021 300 PM GMT Fri Nov 05 2021 Wanda`s cloud pattern has again changed little since the last advisory, with bands of moderately deep convection currently located mainly in the southern semicircle. Just-received ASCAT data indicates an area of 40-45 kt winds mainly west of the center, and based on this the initial intensity is a possibly conservative 45 kt. The ASCAT data also show that the wind field has expanded on the west side, and the initial and forecast wind radii have thus been modified. The initial motion is now south-southeastward or 160/7 kt. A southward motion is forecast during the next 24 h as a mid-level ridge builds to the north and west of the cyclone. After that time, a developing mid-latitude cyclone currently south of eastern Canada will move close enough to break down the ridge and produce southwesterly deep-layer flow around Wanda. This should cause the tropical cyclone to turn northeastward and accelerate, with a quick northeastward motion continuing until Wanda dissipates. The latest track guidance is in good agreement, and the new forecast track lies close to the various consensus models. The southward motion should bring the center over slightly warmer water during the next 24-36 h, and during this time Wanda should be in an area of light to moderate shear inside of the circulation of a nearby upper-level low. This environment should allow Wanda to maintain its strength and perhaps strengthen a little. By 48 h, the mid- latitude system approaching from the west should cause increased shear, although the associated increased upper-level divergence may offset any weakening caused by the shear. Wanda is forecast to merge with a frontal zone by 72 h, and by 120 h the system is forecast to weaken to a tough to the south of a large mid-latitude low over the northeastern Atlantic. The new intensity forecast has only minor adjustments from the previous forecast. FORECAST POSITIONS AND MAX WINDS INIT 05/1500Z 40.6N 37.8W 45 KT 50 MPH 12H 06/0000Z 39.1N 37.7W 45 KT 50 MPH 24H 06/1200Z 37.9N 37.7W 45 KT 50 MPH 36H 07/0000Z 38.2N 36.5W 45 KT 50 MPH 48H 07/1200Z 41.0N 33.1W 50 KT 60 MPH 60H 08/0000Z 45.4N 28.2W 50 KT 60 MPH 72H 08/1200Z 50.0N 22.6W 45 KT 50 MPH...POST-TROP/EXTRATROP 96H 09/1200Z 57.5N 12.0W 40 KT 45 MPH...POST-TROP/EXTRATROP 120H 10/1200Z...DISSIPATED $$ Forecaster Beven |