Monday, March 6, 2017

Winter showing big signs of life but still searching for the big snow we so desperately need

The last update was somewhat of a mental capitulation. The simple process of purging any positive expectations of what remains in our ski season. I say this tongue and cheek but usually when one does this, the weather has a tendency to surprise you. Though we did discuss the possibility of more winter weather in March, our recent struggles certainly have the MRG faithful in an understandably cynical mood. That said, it still looks wintry and even more so according to the last 2-3 days of model data. We can be relatively certain regarding a sustained stretch of cold weather but the question of how much this can translate into needed snowfall remains.


There are a few derogatory thoughts that come to mind regarding the short term forecast but this is a family friendly blog so lets just call it a classic Vermont slap-in-the-face. Temperatures this past Saturday and Sunday were the most anomalous on the cold side since the middle of December ( nearly 20 below normal) yet here we are talking about rain. Precipitation will actually arrive as a bit of freezing rain Monday night and persist as some freezing rain or drizzle early Tuesday. By later Tuesday, temperatures will push past the freezing mark and the mainly light precipitation will become plain rain. This system is tracking well north of us and it will provide us with another, albeit, small window of excessive warmth. It will happen just ahead of the passage of the cold front early Wednesday. So temperatures will continue to warm Tuesday night and we should see a brief period of moderate rainfall. Temperatures will be near 50 Wednesday morning but will fall back into the 30's by evening.


Our first piece of "wintry news" involves the forecast for last Wednesday, Wednesday night and early Thursday. A closer look at stability parameters does reveal that this time frame is a good time frame for terrain enhanced snowfall; in fact, convective snow showers should dot much of northern New England in this time frame including valley locations. The high country should get a round of accumulating snow. By late in the day Thursday, 4-8 inches is my best guess for MRG with higher amounts farther north.


The next piece of wintry news comes Friday and into the weekend. This period looks substantially colder compared with expectations presented in the last update. The block across the Bering Sea has allowed arctic air to pool quite impressively across northern Canada with -40 to -60 degree readings as of Monday. Models had been oscillating and hedging as to what areas of the continent would get the impact of this air but New England will indeed see it. The polar vortex responsible for this cold will actually drop into Quebec this Friday and dissipate across the eastern Canadian Maritimes late in the weekend. Though it will be cold with a fresh few inches of snow, the presence of the PV will actually push the storm track southward during this period. One weak system over the Mid Atlantic will bring some light snow to some of the big city locations early Friday but aside from flurries Thursday night, much of Vermont will be on the dry and cold side Friday. Daytime temperatures will be in the 20's Friday and only in the teens Saturday and much of Sunday. Meanwhile another significant storm will pass well to our south over the weekend and is likely to prove to be the biggest snow producer many Mid Atlantic locations and ski areas have seen all season. Many of these Mid-Atlantic ski areas have already shut down for the season.


The weekend storm, that we are likely to miss isn't the only game in town however. There is one to perhaps two additional storms in the following week that could bring substantial amounts of wintry weather to Vermont. This happens as the PV escapes and the pattern relaxes somewhat early next week. One storm of intrigue should impact the region in the March 14th to March 15th time frame while another should follow around the time of March 18th and 19th. Teleconnection indices, though not overwhelming remain supportive enough ensure that at least some arctic air will remain in play though ensembles do disagree as to how much. For the time being however, the presence of the large block in the Bering Sea over a gentler but active Pacific Jet will make it interesting at least though I certainly will not and could not guarantee that every outcome will be a great one.

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