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#1024944 (Received by flhurricane at: 4:00 AM 12.Nov.2020) TCDAT5 Tropical Storm Theta Discussion Number 10 NWS National Hurricane Center Miami FL AL302020 900 AM GMT Thu Nov 12 2020 Theta currently is comprised of a large swirl of low- to mid-level clouds with no convection near the center. However, a band of convection is wrapped about three-quarters of the way around the center at a distance of about 200 n mi in the eastern semicircle and 100 n mi in the western semicircle. Overall, the cyclone has somewhat of a subtropical appearance at this time. Since there has been no data from the cyclone`s core region since the last scatterometer pass, the initial intensity is held at 55 kt. The storm continued to jog a little to the left since the last advisory, but the last few satellite images suggest a more eastward motion has resumed. The initial motion is a somewhat uncertain 060/10. For the next 24 h or so, Theta is expected to continue to move east-northeastward as it rounds the north side of a mid-level ridge centered over the Cabo Verde islands. An eastward to east-southeastward motion is expected from 24-72 h as the mid-level ridge to the south weakens and mid- to upper-level northerly flow moves over the cyclone. After that time, Theta or its remnants is expected to be steered northeastward in the low-level flow to the southeast of a deep-layer mid-latitude cyclone over the northeastern Atlantic. The new forecast track is adjusted north of the previous track based on the initial position and motion, and it lies near the various consensus models. Theta is forecast to change little in intensity during the next 36 h or so as it moves into the light shear area near an upper-level trough axis. After that time, the trough moves south of the cyclone, and strong northerly vertical shear should occur along with the entrainment of stable air. This combination should cause Theta to quickly weaken, and the intensity forecast calls for the system to decay to a remnant low pressure area by 96 h. The new intensity forecast has only minor adjustments from the old forecast, and it lies a little above the intensity consensus. FORECAST POSITIONS AND MAX WINDS INIT 12/0900Z 31.7N 30.2W 55 KT 65 MPH 12H 12/1800Z 32.0N 28.5W 55 KT 65 MPH 24H 13/0600Z 32.3N 26.2W 55 KT 65 MPH 36H 13/1800Z 32.3N 24.0W 55 KT 65 MPH 48H 14/0600Z 32.0N 22.1W 50 KT 60 MPH 60H 14/1800Z 31.7N 20.8W 40 KT 45 MPH 72H 15/0600Z 31.6N 20.1W 35 KT 40 MPH 96H 16/0600Z 33.0N 19.5W 30 KT 35 MPH...POST-TROP/REMNT LOW 120H 17/0600Z 37.0N 18.0W 30 KT 35 MPH...POST-TROP/REMNT LOW $$ Forecaster Beven |