Some snow Monday night is followed by a heavy rain event Wednesday

Mad River Glen has been on a roll, scoring a few inches of snow on nearly a daily basis over the past 5 days. This stretch of weather gets capped off with a final few inches of snow, all coming in a span of a few hours Monday evening. Even as warm air encompasses much of the eastern Great Lakes region, sub-freezing temperatures will remain entrenched across northern Vermont through early Tuesday. The snow Monday evening is of the front-end thump variety, as a wave of low pressure, passing to the region's south, marks the advance of the milder temperatures with an accompanying area of precipitation. Snowfall totals will be in the familiar 2-4 inch range and though it might fall as powdery snow, Tuesday's near freezing temperatures will make this consistency a little wetter. Much of Tuesday is precipitation free, but the mid-level temperature environment is expected to warm considerably even as surface temperatures hover around the freezing mark. By the end of the day, a stronger area of low pressure will organize over the southeastern United States and as this strengthening storm travels northward, much of the cold will  have been scoured out of interior New England. 

December has always been a tricky month for winter weather in New England. Even with favorable weather pattern, the proximity of all that relative Atlantic Ocean warmth leaves the region so vulnerable to the rogue inland runner and a big temperature surge. Such is very much the case with the rain event set to smack us in the face on Wednesday. The track of this storm isn't even that bad with the current expectation having the primary low track very close to us Wednesday evening. The lastest Euro, released right at the time of this update has the track of the low east of us over New Hampshire which would be good enough for a colder storm and some snow on the back end, yet mostly we would still be wet. The low pressure center in question begins to take shape across over the southeast early Tuesday and strengthens quickly over the Ohio Valley, continuing to intensify on its track toward northern New England. The fact that this storm will have not reached maturation upon its arrival opens the door for the northward push of low and mid level tropospheric warmth. Light rain or freezing rain in some areas begins Tuesday night and becomes a steadier and then heavier rain on Wednesday with temperatures gradually warming toward 40 degrees. Depending on the eventual track of the low, there is the potential for a brief but intense temperature spike for a few hours Wednesday evening. We might avoid this if the low pressure area tracks over New Hampshire, but either way, we won't avoid the heavy rain which will amount to well over an inch and then change to snow early Thursday before ending. Colder weather appears more intense Thursday and Friday with readings in the 20's on the former (with gusty winds) and perhaps only in the teens during the latter. Single digit readings are possible during each of the upcoming weekend mornings though wind is expected to subside and sunshine is expected for at least the Saturday portion. 

There is a nice looking cold air damming signature beginning to show its face on model simulations Sunday and this does indicate the possibility for an east coast winter storm. Whether or not the impact of such an event could reach far enough into northern Vermont is a tough question. I would call it unlikely right now but stay tuned. 

The longer range outlook which includes both next week and the following week continue to improve. The general consensus continues to point toward a milder period early next week but this milder weather has looked considerably less intense over time and there are no signs of rain of any significance. Multiple ensembles show colder air making a return late next week and likely consuming the region for solstice weekend. Though the ensembles aren't indicating a strong signal one way or another for Christmas week, I am very encouraged with the EPO which is again expected to turn very negative in two weeks time. This combined with a mildly negative AO favors colder and snowier conditions in New England. We've had the misfortune of many rainy Christmas weeks over the past several years. To say we are due for something better would be an understatement !