A rational perspective on the dynamics
I see rumblings in the media and social media... "Maine is getting a tropical storm!" and I just sigh deeply. Yes, Philippe is tropical, but that is going to change. By the time it gets into the Gulf of Maine airspace, it'll be a NorEaster, and an intensifying one at that. The only thing that will be tropical about it is the moisture hose attached to it. The region is not getting a tropical storm, there will be no tropical storm related bulletins issued for mainland areas, and there is no reason to panic because of it. It will ruin some outdoor plans, but that is about it. Here's some inside baseball for you... "post-tropical storms" are NorEasters, pending on which side of the wind field you happen to be.
Maine is in the convergence zone where the trough and remnants of Philippe will interact. There is a quite the game of liar's poker going on with operational models, but the short-term models have a better handle on it and show better consistency.
Phillipe is getting torn to shreds
This graphic here shows Philippe heading for the cabbage shredder as shear outlined by the red contours. It's a tropical storm, but from an aesthetics view, it's been chopped in half and the warm core is exposed. It'll maintain tropical characteristics until Saturday morning, but between the shear and colder ocean water, it will flip to a cold core system and get revved up by the approaching front and associated negative trough.
A wider view shows the approaching front and the west side of Philippe from this loop in the wee hours of Friday morning. If you notice the greens and blues popping up to the southeast of Cape Cod, this is the beginning of the interaction between the front and Philippe, the predecessor rain event (PRE) set up I've discussed over the past couple of days.
While the trough is deep and strengthening, Philippe is taking its time heading north. At this point early Friday morning, the two main features appear to be delayed with their convergence. This sets up split results for Maine.
Timing, rain, and wind
Friday 3 PM to Saturday 3 PM - A few outflow showers are possible across the region Friday into Friday night. Showers are expected to become more numerous heading into Saturday morning. There could be a bit of lull Saturday afternoon over southern areas as the moisture with Philippe begins to move into the Gulf of Maine. The wind will gradually pick up as the front and storm interact more with one another.
Saturday 3 PM to Sunday 1 PM - The fire hose with Philippe brings heavy rain and stronger wind for the Penobscot Bay region eastward heading into Saturday night. As the remnants of Philippe draw to the northwest into the developing upper-low over western Quebec, the faucet shuts off from southwest to northeast during the morning on Sunday, with showers ending over northern and far eastern areas Sunday afternoon.
I am not a fan of showing model progs for precipitation amounts, but in this case it's important to highlight what could be a very sharp cutoff with rainfall totals. The idea of the higher amounts for the western mountains and eastern and northern areas continues as that has been consistent. Southwestern areas could see locally 1-2", but most areas appear to escape with less than 1".
I still can't dismiss the idea of the predecessor rain event possibly throwing up higher totals for southwestern areas, so there is still the chance for overperformance.
Localized flash flooding from heavy rain, urban street flooding from clogged storm drains from leaf drop, along with low visibility from the rain and fog are all hazards to consider for travelers. Folks with sensitive basements will need to monitor them closely.
A slight adjustment to the forecast maximum wind gusts, Folks along the DownEast coast, especially coastal Washington County are likely to get the stronger gusts. I put 40+ for Eastport, and there are cases being made for 50+ there, so folks there should be aware of that. The best chance for power outages is for eastern areas, but this Maine and we know how that goes. Spotty outages could happen anywhere. Be prepared in case power is lost.
I need your help to keep PTW going
Thank you for your years of readership and for your financial support. It is because of you that this operation continues.
Stay updated, stay on alert, and stay safe!
NOTE: The forecast information depicted on this platform is for general information purposes only for the public and is not designed or intended for commercial use. For those seeking pinpoint weather information for business operations, you should use a private sector source. For information about where to find commercial forecasters to assist your business, please message me and I will be happy to help you.