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| #1062146 (Received by flhurricane at: 10:42 PM 17.Sep.2021) TCDAT5 Tropical Storm Odette Discussion Number 2 NWS National Hurricane Center Miami FL AL152021 1100 PM EDT Fri Sep 17 2021 Satellite images indicate that west-southwesterly shear is taking a toll on Odette. Deep convection has been separating from the low-level circulation, and the closest area of thunderstorms is now more than 100 miles east of the center. The circulation is rather broad, but there is a clear center a couple of hundred miles off the U.S. Mid-Atlantic coast. The initial intensity is held at 35 kt for this advisory. A very recent ASCAT pass showed some stronger winds in the thunderstorms more than a couple of hundred miles east of the low-level center, but its not clear if those winds are reliable and representative of the storm`s true intensity. Hopefully more scatterometer data with be available soon to better assess Odette`s strength. Although it appears that Odette has been meandering lately, a 12-hour average yields a northeastward motion at about 9 kt. The storm is expected to move faster northeastward or east-northeastward off the northeast U.S. and Atlantic Canada coasts this weekend as it moves in the mid-latitude flow. After that time, the models show a significant slow down as the cyclone cuts off from the progressive flow to the south or southeast of Newfoundland. Although there is quite a bit of spread in the models from days 3-5, almost all of the guidance shows the storm stalling by the end of the forecast period. The new NHC track forecast is a little to the south of the previous one to come into better agreement with the latest models. This forecast still lies to the north of the consensus aids, however. Odette is already beginning the process of transitioning to an extratropical cyclone, and it will likely complete the transition by Saturday night when it is expected to be north of the Gulf Stream Current and merging with an approaching trough. The cyclone is likely to reach its peak intensity as an extratropical storm in 48-60 hours when the baroclinic dynamics are most favorable. Gradual weakening seems likely beyond that time. The NHC intensity forecast is the same as the previous one and in line with the majority of the guidance. As Odette becomes fully extratropical and gains latitude this weekend, the wind field is forecast to expand significantly. Odette is expected to affect portions of Newfoundland with strong winds and heavy rainfall Sunday and Sunday night as a post-tropical cyclone. Please refer to products from Environment Canada for additional information on potential impacts in Newfoundland. FORECAST POSITIONS AND MAX WINDS INIT 18/0300Z 36.4N 71.2W 35 KT 40 MPH 12H 18/1200Z 37.8N 69.3W 40 KT 45 MPH 24H 19/0000Z 39.4N 65.7W 45 KT 50 MPH...POST-TROP/EXTRATROP 36H 19/1200Z 41.0N 61.7W 50 KT 60 MPH...POST-TROP/EXTRATROP 48H 20/0000Z 42.3N 57.5W 55 KT 65 MPH...POST-TROP/EXTRATROP 60H 20/1200Z 43.4N 53.1W 55 KT 65 MPH...POST-TROP/EXTRATROP 72H 21/0000Z 43.8N 50.0W 50 KT 60 MPH...POST-TROP/EXTRATROP 96H 22/0000Z 44.3N 48.0W 45 KT 50 MPH...POST-TROP/EXTRATROP 120H 23/0000Z 44.8N 46.6W 35 KT 40 MPH...POST-TROP/EXTRATROP $$ Forecaster Cangialosi |