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The first widespread snow for Maine is coming... but is Friday the day?
Many questions to be answered
I shared this on Twitter earlier in the day Monday as I began to sift through data. Three obvious pieces here. The cold over Alaska, the upper level low over the southwest, and Zeta. All three of these ingredients are important pieces in how this comes together... or not.
All three of these pieces need to come together by Thursday. High pressure needs to move fairly quickly from northern Alaska and be in central Ontario. This will supply the cold, and assist to navigate the storm. The upper low over the southwest needs to swing to the central part of the Midwest, which supplies the energy. Zeta will provide moisture for the system. It will have to survive the Yucatan Peninsula, then move along at a decent pace to meet up with the energy from the upper low and form a storm by Thursday morning.
We're dealing with cold air, which is more dense and moves slow. We're also dealing with an upper level low located in the southwest, which has been a blind spot for the European model for years that it can't seem to solve right. Then we have Zeta, which since it is tropical in nature, which has its hurdles to deal with.
Despite all the snowfall maps that get tossed around on social media, the ones that matter at this point are the ensemble percentage ideas, given the storm potential is still four days out.
It makes a difference when you cut through the model foolishness and get under the hood with ensembles.
This is a "Probability of 24-hour Snowfall at 10:1 ratio (snow to water) ≥ (greater than or equal to) 1 INCH." I am stressing INCH here to make a point. This ensemble idea by the European thinks there is LESS THAN a 100% chance of ONE INCH OR MORE of snow. That doesn't give me the fuzzies to think something big is going to happen here. I need to see deep red which indicates the model is thinking it's a virtual lock for ONE INCH of snow. We're not there yet.
The Canadian ensemble as of the Monday morning run was even less interested in what is going on. A 20-30% chance for "Probability of 24-hour Snowfall at 10:1 ratio (snow to water) ≥ (greater than or equal to) 1 INCH" at best.
The point is there are caution flags flying all over the place with this one. The truth be known is no one model has this potential storm figured out. I know for you plow people and folks who want the snow may not like my dissection of this, but I would rather you know the facts at this point than not.
This can and will likely change. Whether the chance increases or decreases, it is too early to tell. We'll see how Zeta fairs after the trip through the Yucatan, how the cold progresses, and how models figure out the upper low over the southwest.
In the meantime, get your appointment booked to get your snow tires put on. Winter is coming, regardless if it happens Friday or at some other point in the near future.
Stay tuned for updates.
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