Tuesday, January 2, 2024

Light accumulations of snow and sub-freezing temps through the weekend while we watch and hope for the right kind of storm next week

The sun didn't show up like I thought it would on New Year's day, but it was nice to see temperatures miss expectations to the cold side, something that didn't occur much in December. The sun has shown up for Tuesday, the first official business day of 2024, which should feature some of the best visibility in 10 days. There are a lot of potential storms that should, at the very least bring more cloudy days to Vermont in the coming weeks, but we should at least have a brief reprieve that will last through about half of Wednesday. 

New snow arrives on Thursday with the return of some arctic air. I have big welcome mat set out for the airmass and I am very happy to see the North American  continent build a very healthy pool of arctic chill over the next week. The polar airmass on Thursday just grazes us but the clipper system responsible for its arrival will bring some limited moisture and turn winds in a favorable direction for enhanced terrain induced snow showers and squalls. We should get a bit of both on Thursday and 1-4 inches of resulting snow. In the next day or so, I can better assess if there is some potential for more as the high resolution short term models better clarify the stability parameters, wind and how long we have the favorable setup for the aforementioned snow. Accumulations will mostly be confined to the high country, but snow squalls will be possible anywhere and it certainly will be cold enough to accumuulate everywhere with temperatures generally in the 20's on Thursday. 

Single digit temperatures and blue sky will be the story for Friday, a day that will start a little blustery but should finish with diminishing winds. On the mountain temperatures will struggle to get past 20 in spite of that sunshine. Blue skies are expected to linger through early Saturday before clouds overtake us. As expected chatter regarding an east coat snow storm has increased. Many areas in the path of this storm (I 95 corridor) haven't seen significant snow since 2022 so that area has a good chance of breaking the drought. Northern Vermont does not appear to be in the best spot for heavy snow with this event, though the MRV should receive some snow beginning after midnight Sunday and continuing through part of the daylight hours. With a few days still to go before this event commences, there remains time for northward shifting. It would be beneficial for snowfall because of a better track obviously, but northward shifting is also a natural result of a more intense storm. Not a likely scenario right now, I would keep expectations in the 2-6 inch category, but not off the table either. 

The pattern fundamentals are slowly improving but the Pacific jet stream / EPO index remains a little problematic next week and it results in a clash of competing forces. Energy from the Pacific will allow an intense storm to form near the eastern Rockies in the Sunday/Monday time frame. The early maturation of this storm, a common theme when the Pacific gets overcharged, is likely to result in a major low pressure area tracking toward the Great Lakes and looking to attain "inland runner" status before impacting Vermont late Tuesday into Wednesday of next wee (Jan 9 & 10). As I've mentioned in prior posts, we do have downstream blocking that should help prevent such an outcome and allow for snowfall to remain a possibility. Though we saw some of the medium range models move in that direction today, a wetter, windy outcome remains on the table if one is to believe data from the Euro. Don't get too discouraged on this one yet, a lot of possibilities remain. 

The Pacific is indicated to weaken after the passage of the aforementioned storm  and by the end of next week, some of the strongest cold in the northern hemisphere will position itself over Canada. This is quite a shift from the torch-a-thon much of Canada saw last month. How, when and where this cold descends on the U.S. remains to be seen but as I mentioned, the pattern fundamentals continue to support the southward transport of at least some of this cold. The continued strength of El Nino and the continued rigor of the southern stream of the jet stream can be a natural blockade so it would help if Nino would weaken some which it has showed signs of doing in eastern equatorial regions. Still though, Nino 3.4 readings of nearly 2 C above average is formidable. We may have peaked but haven't come down the slope too far as of yet.

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