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Hurricane Paulette Forecast Discussion Number 36
2020-09-15 22:35:47| National Hurricane Center (Atlantic)
Issued at 500 PM AST Tue Sep 15 2020 000 WTNT42 KNHC 152035 TCDAT2 Hurricane Paulette Discussion Number 36 NWS National Hurricane Center Miami FL AL172020 500 PM AST Tue Sep 15 2020 Another fortuitous AMSR2 microwave pass over the cyclone showed the outer concentric ring open over the south semicircle and a more noticeable vertical tilt. Furthermore, the cloud tops associated with the deep convection in the north quadrant have warmed during the past several hours. Consequently, the initial intensity is lowered to 85 kt and is in best agreement with the subjective and objective satellite intensity estimates. Paulette continues to lose its tropical characteristics as it mingles with the rapidly approaching baroclinic zone from the northwest. In fact, earlier successive METOP A and B scatterometer passes on Paulette revealed that the northwest quadrant 34-kt wind radii had nearly doubled in size due to the aforementioned invading frontal zone moving out of the Canadian Maritimes. The sea surface temperatures quickly decrease to less than 20C within 24 hours as Paulette accelerates east-northeastward. As a result, the cyclone should weaken rather quickly and complete its extratropical transition on Thursday, as indicated in the global models and the statistical-dynamical guidance. Paulette is moving east-northeastward, or 060/26 kt, and this motion should continue with a further increase in forward speed through Thursday. Toward the end of the week, the cyclone will likely turn south-southeastward to southward as it moves within the western peripheral flow of a mid- to upper tropospheric cut off low to the east of the cyclone. The NHC track forecast is basically an update of the previous advisory and is based on the various consensus guidance. The initial wind radii and subsequent forecast wind radii were adjusted based on METOP A/B ASCAT 1110 UTC and 1424 UTC scatterometer passes. FORECAST POSITIONS AND MAX WINDS INIT 15/2100Z 39.5N 55.0W 85 KT 100 MPH 12H 16/0600Z 41.4N 50.1W 80 KT 90 MPH 24H 16/1800Z 44.0N 42.9W 70 KT 80 MPH 36H 17/0600Z 45.8N 36.8W 55 KT 65 MPH...POST-TROP/EXTRATROP 48H 17/1800Z 45.8N 33.7W 50 KT 60 MPH...POST-TROP/EXTRATROP 60H 18/0600Z 43.9N 32.8W 45 KT 50 MPH...POST-TROP/EXTRATROP 72H 18/1800Z 41.2N 32.8W 40 KT 45 MPH...POST-TROP/EXTRATROP 96H 19/1800Z 38.0N 32.5W 35 KT 40 MPH...POST-TROP/EXTRATROP 120H 20/1800Z 34.5N 32.3W 35 KT 40 MPH...POST-TROP/EXTRATROP $$ Forecaster Roberts
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