The coldest air so far this season and the first real Arctic airmass arrives in Maine this weekend and on either side of it we have storm threats. Lets start with the first one which is on Saturday as the bitter cold moves in.
The cold front that actually delivers the bitter cold air moves offshore Saturday morning and sets up cold NW flow over the area Saturday. Meanwhile, warmer air (relatively speaking) lurks offshore. This boundary will wrap around the eastern side of a powerful upper low that moves to out south. How far west that boundary gets and exactly where it sets up are the two big questions with the forecast this evening. Right now, the midcoast has the best chance to see a solid snowfall out of this event. 4-8″ are possible there. Amounts drop off sharply to the west where a coating-2″ is likely with squalls similar to those today though probably more widespread (Portland likely shares the goods with the rest of us more evenly). Winds will be busy though the whole event so blowing, drifting, reduced visibility, and all the other standard impacts for wind-driven fluff are likely.
Following this storm, bitter cold arrives for Sunday. Wind chills of 50-60 below are possible in the mountains Sunday morning as temps fall well below zero and NW winds howl. More blowing and drifting snow is likely during this time. For the first time on Sunday, it will truly feel like winter in Maine. For those winter haters out there, don’t worry, El-Torcho comes back to some extent on Tuesday as low pressure either passes over us or to our west.
The current thinking is that a storm forms on the back side of the bitter cold and moves either over us or to our west, leaving us with a messy storm rather than straight snow. However, notice the individual solutions (little red ‘L” markings) range from out to sea (the one by Nova Scotia) to snow (the cluster off the coast) to a mix (the ones over us) to rain (the cluster well west). All possibilities remain on the table at this point though some sort of mix is most likely.
I’ll have more updates tomorrow.