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| #984240 (Received by flhurricane at: 4:54 AM 27.Sep.2019) TCDAT2 Tropical Storm Karen Discussion Number 21 NWS National Hurricane Center Miami FL AL122019 500 AM AST Fri Sep 27 2019 Karen`s status as a tropical cyclone is becoming increasingly dubious. In a trio of ASCAT passes that arrived yesterday evening, the circulation of the cyclone was indistinguishable from a surface boundary that extends south from the remnants of post-tropical cyclone Jerry. This suggests that Karen`s circulation may no longer be well-defined. Furthermore, deep convection near the center of Karen has generally decreased and become less organized since last night. Satellite-based intensity estimates support maintaining the intensity of Karen at 35 kt, but this could be generous given that the max winds observed in the earlier ASCAT data were lower. Regardless of the exact starting intensity of the cyclone, gradual weakening is expected for the next few days. There is unanimous agreement among the dynamical models on this scenario. Simulated satellite imagery from the GFS and ECMWF models show the cyclone devoid of deep convection within 36 hours, if not sooner. Increasingly hostile upper-level winds should then prevent the cyclone from reorganizing and it is forecast to dissipate in about four days. It has been difficult to locate the center of Karen overnight and the initial motion estimate is uncertain but also unchanged (055/7 kt). The global models are forecasting that Karen will continue to move on this general heading through this morning before it stalls tonight. A building ridge to the north should cause Karen or its remnants to start moving westward over the weekend. FORECAST POSITIONS AND MAX WINDS INIT 27/0900Z 28.3N 61.2W 35 KT 40 MPH 12H 27/1800Z 28.8N 60.1W 35 KT 40 MPH 24H 28/0600Z 29.1N 59.6W 30 KT 35 MPH 36H 28/1800Z 29.3N 60.1W 30 KT 35 MPH...POST-TROP/REMNT LOW 48H 29/0600Z 29.3N 61.3W 25 KT 30 MPH...POST-TROP/REMNT LOW 72H 30/0600Z 29.0N 64.5W 25 KT 30 MPH...POST-TROP/REMNT LOW 96H 01/0600Z...DISSIPATED $$ Forecaster Zelinsky |