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Hurricane Marie Forecast Discussion Number 22
2020-10-04 16:45:13| National Hurricane Center (East Pacific)
Issued at 800 AM PDT Sun Oct 04 2020 000 WTPZ43 KNHC 041445 TCDEP3 Hurricane Marie Discussion Number 22 NWS National Hurricane Center Miami FL EP182020 800 AM PDT Sun Oct 04 2020 Conventional satellite imagery reveals an increasingly apparent asymmetric/vertical tilt due to persistent west-southwesterly shear. The surface center is beginning to become exposed and is now near the western edge of the deep convective mass. The initial intensity is lowered to 80 kt for this advisory and is based on a compromise of the available subjective and objective satellite intensity estimates. Weakening should continue rather quickly through the forecast period while the shear magnitude increases with time and the cyclone traverses cooler oceanic surface temperatures. Marie should degenerate to a post-tropical remnant low in 3 days, or less, and this is in agreement with the majority of the global/regional and statistical guidance. The intensity forecast is near the IVCN intensity consensus and above the ECMWF and GFS Decay SHIPS which actually show dissipation in less than 4 days. Maria's initial motion is estimated to be northwestward, or 315/6 kt, within the mid-tropospheric steering flow provided by a subtropical ridge anchored to the north of the cyclone. Marie should continue moving in either a west-northwestward or northwestward motion through the remainder of forecast period with some reduction in forward speed, day 3 and beyond. The NHC forecast track has been adjusted a little bit south of the previous advisory after the 24 hour period in order to be closer to the various multi-model consensus aids and to conform more with a motion typical of a shallower, vertically limited system moving through the trade wind flow. FORECAST POSITIONS AND MAX WINDS INIT 04/1500Z 20.3N 128.6W 80 KT 90 MPH 12H 05/0000Z 20.7N 129.5W 65 KT 75 MPH 24H 05/1200Z 21.3N 131.0W 55 KT 65 MPH 36H 06/0000Z 22.0N 132.3W 45 KT 50 MPH 48H 06/1200Z 22.7N 133.9W 35 KT 40 MPH 60H 07/0000Z 23.4N 135.2W 30 KT 35 MPH 72H 07/1200Z 24.0N 136.0W 30 KT 35 MPH...POST-TROP/REMNT LOW 96H 08/1200Z 24.8N 136.9W 25 KT 30 MPH...POST-TROP/REMNT LOW 120H 09/1200Z 25.3N 137.9W 25 KT 30 MPH...POST-TROP/REMNT LOW $$ Forecaster Roberts
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