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#1159241 (Received by flhurricane at: 5:01 AM 28.Oct.2023) TCDAT5 Tropical Storm Tammy Discussion Number 36 NWS National Hurricane Center Miami FL AL202023 500 AM AST Sat Oct 28 2023 Tammy continues to be a sheared system with limited convection this morning. Cloud tops have been warming since last evening, with only occasional burst near the center. A partial scatterometer pass that arrived shortly after the previous advisory, depicted winds on the eastern side of the system were 40-45 knots. This ASCAT data is in good agreement with the latest TAFB satellite intensity estimate of T3.0/45 kt. Therefore, the initial intensity is lowered to 45 kt based on this data and the degraded satellite presentation. Strong vertical wind shear is expected to continue over Tammy the next few days, which should result in further weakening. While sea surface temperatures are marginal, there is increasingly dry air along the forecast track. The GFS and ECMWF model-simulated satellite data indicate Tammy could be completely devoid of convection within 36- 48 hours. The updated NHC intensity forecast is lower than the previous one, following the latest consensus aids. Post-tropical remnant low status is now shown in 48 h, although this could occur even sooner than forecast. Tammy has turned northward and then northeastward overnight. The long-term motion of Tammy is northeast at 50/6 kt. A faster eastward to southeastward motion is forecast throughout the weekend as Tammy moves around the northern and eastern sides of a mid-level ridge. As the cyclone weakens and becomes more shallow it is forecast to slow down and turn southward-southwestward early next week as the ridge becomes positioned to its west. The NHC track forecast is a little faster than the previous, and lies between the simple and corrected consensus aids. FORECAST POSITIONS AND MAX WINDS INIT 28/0900Z 33.0N 60.1W 45 KT 50 MPH 12H 28/1800Z 33.0N 58.7W 40 KT 45 MPH 24H 29/0600Z 32.6N 56.0W 35 KT 40 MPH 36H 29/1800Z 31.7N 53.1W 35 KT 40 MPH 48H 30/0600Z 30.4N 50.6W 30 KT 35 MPH...POST-TROP/REMNT LOW 60H 30/1800Z 28.9N 49.5W 25 KT 30 MPH...POST-TROP/REMNT LOW 72H 31/0600Z 27.5N 50.8W 20 KT 25 MPH...POST-TROP/REMNT LOW 96H 01/0600Z 27.9N 53.1W 20 KT 25 MPH...POST-TROP/REMNT LOW 120H 02/0600Z...DISSIPATED $$ Forecaster Kelly |