Arctic air is set to make a temporary return to Vermont late this weekend following the passage of another clipper system on Saturday. I am not optimistic about performing on snowfall from this system. The southwest wind is not a great wind direction in terms of receiving snowfall for several reasons. The most obvious one being the milder flow which in Saturday's case will be especially mild in valley locations given the airmass is Pacific in nature. Temperatures in the valley's will be well into the 40's and any precipitation in the morning could very well fall as rain or just mixed rain and snow. Well up on the mountain we could see an inch or two of snow but even this accumulation might be confined to above the mid-station. The cold front will sweep through the MRV late in the afternoon and send temperatures back below the freezing mark during the evening with some accompanying snow flurries. Maybe we can squeeze another inch out on the mountain Saturday evening but it does not appear especially unstable with the arrival of arctic chill. Models are indicating some cloudiness Sunday but I think storminess off the New England coast will help suck some of that overcast eastward and and allow for some sunshine and decent visibility especially in the afternoon to accompany the near 10 degree temperatures. I think the milder southwest breeze on Saturday (near 20 mph) will be a bit stronger than the cold northwest breeze (10 mph) on Sunday .
Cold temperatures will prevail over Vermont through Wednesday morning with the coldest daytime temperatures of 5-10 degrees occurring on Monday. Both Monday and Tuesday should feature decent amounts of sunshine, but there is a weak polar jet disturbance that is likely to spread clouds and may bring some light snow to northern Vermont early Tuesday. We remain fearful of the milder push of temperatures late next week and this should mean more cloudiness on Wednesday as temperatures attempt to reach the freezing mark during the afternoon.
At face value, the situation does not look good late next week. There is a pretty clear consensus of model data indicating an intense surge of warm weather and some wind and rain in the Thursday/Friday time frame. 50-degree temperatures and some 40-degree dewpoints would be possible in this scenario and when this is combined with any wind, it can eat snow at a very efficient rate. With that said, the setup does show some similarities to to what occurred on February 3rd/4th with the key difference being that the storm track is appears 100-150 miles farther north. As models have trended milder in southern New England late next week, they have also moved to solidify the the presence of arctic chill over much of a Quebec with the storm in question tracking south of the St Lawrence Valley and possibly producing a big snowfall in cities such as Montreal. We are no longer asking for a huge shift in the data to produce a drastically different result late next week. 100 mile shift to the south or even just a flatter jet stream setup could greatly alter the results and change the forecast much like what happened early in the month. Not going to call it likely but there is hope of another escape and I do expect models to shift and at least partially mitigate what they are now indicating to be a significant thaw.
A return to colder weather can be expected for the President's Day holiday weekend and I've seen a few the operational models paint interior New England with some snowfall over that stretch. Again however, the arctic chill appears temporary in nature and is expected to give way to milder temperatures early in the last full week of February which is a holiday week for many. None of the teleconnection indicators appear to be on our side in late February but the biggest concern to me is the angrier Pacific driven by what appears to be a mild MJO phase we are plunging into.
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