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000 WTNT42 KNHC 061454 TCDAT2 Post-Tropical Cyclone Philippe Discussion Number 53 NWS National Hurricane Center Miami FL AL172023 1100 AM AST Fri Oct 06 2023 The center we were following overnight has become untrackable this morning and appears to have become absorbed by the nearby frontal zone. In addition, the overall cloud pattern now has the look of a classic extratropical cyclone, with Philippe's center resembling the triple point of an occlusion. Based on these recent developments, Philippe is being declared a post-tropical cyclone. The intensity remains 45 kt, mainly based on continuity. The initial motion is estimated to be north-northeastward, or 020/14 kt, but this movement is becoming less representative as the larger storm system takes over. Philippe's remnant center and another non-tropical low to the west are likely to interact and/or merge with each other during the next day or two, but the overall system is expected to move northward or north-northwestward at increasing forward speed into the weekend. This will bring the center of the post-tropical cyclone to the coast of Nova Scotia or Maine in about 48 hours, and then inland toward eastern Quebec before it becomes absorbed by a separate but larger extratropical low. The post-tropical cyclone still has an opportunity to strengthen a bit over the next day or so due to baroclinic influences. Due to the system's structure and forward motion, the strongest winds are expected to be on the eastern side of the circulation and will most likely affect portions of Atlantic Canada. Weakening is forecast after the system moves inland. Future information on potential flooding impacts in the Northeast United States can be found in products issued by the Weather Prediction Center on the web at http://www.wpc.ncep.noaa.gov, and in products issued by local National Weather Service Forecast Offices on the web at http://weather.gov. Additional information on marine impacts can be found in High Seas Forecasts issued by the National Weather Service, under AWIPS header NFDHSFAT1, WMO header FZNT01 KWBC, and online at ocean.weather.gov/shtml/NFDHSFAT1.php. KEY MESSAGES: 1. The post-tropical cyclone is expected to move over portions of Atlantic Canada and New England this weekend. Interests in those areas should be prepared for the possibility of strong winds and heavy rainfall and monitor statements from their local weather office. The rainfall may produce isolated to scattered instances of urban and flash flooding. FORECAST POSITIONS AND MAX WINDS INIT 06/1500Z 30.7N 64.6W 45 KT 50 MPH...POST-TROP/EXTRATROP 12H 07/0000Z 33.1N 64.9W 45 KT 50 MPH...POST-TROP/EXTRATROP 24H 07/1200Z 36.3N 66.0W 50 KT 60 MPH...POST-TROP/EXTRATROP 36H 08/0000Z 40.0N 66.3W 50 KT 60 MPH...POST-TROP/EXTRATROP 48H 08/1200Z 44.9N 67.5W 45 KT 50 MPH...POST-TROP/INLAND 60H 09/0000Z 49.1N 70.9W 35 KT 40 MPH...POST-TROP/INLAND 72H 09/1200Z...DISSIPATED $$ Forecaster Berg | |
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