Saturday, February 9, 2019

It's pretty firm out there, but modest amounts of new snow is starting to enter the more immediate horizon

We've concluded a rough first week of February and have survived that week with good coverage. As loyal skiers of MRG can certainly attest, we've certainly come out of thaw/rain events in worse shape. Looking forward, we certainly have some things going for us and some relief on the immediate horizon but the PNA (Pacific - North America Oscillation) has been and will continue to be problematic for a time. Simplistically speaking, the PNA is a measure of the pattern across western North America. When the index is negative, the western United States is cold, unsettled and much of the ski areas out that way are living large. A positive index, such as the one we enjoyed throughout much of February 2015, focuses the warm and dry weather out west while persistent cold is envelops eastern North America.

All that being established, colder weather has returned to Vermont and really hardened snow conditions. The chill along plenty of sunshine is expected to prevail not only for the duration of the weekend, but into Monday as high pressure is expected to remain in control across much of northern New England even as weak area of overrunning precipitation impact areas farther south. Southern Vermont could see more cloudiness and a period of very light snow Sunday night but even down there, it won't amount to much. 

If one is to take a brief glance at the main NWS home page , the coverage of winter weather related advisories and warnings out west would be the first thing to jump out at you. The storm responsible for most of that is still headed in our direction for the middle of the week. If there has been a trend in some of the expectations over the past 48 hours, it suggests a stronger, juicier but also warmer system for northern Vermont. Precipitation would arrive late in the day Tuesday and it does appear that a period of heavier snow is possible for a time Tuesday evening into early Tuesday night. This snow hound continues to hope that the coastal low pressure that is expected to form Tuesday evening off the Jersey coast, will intensify more explosively and focus much of the snowfall over interior New England for an extended period of time. Though this remains a possibility it is not the current indication and thus a more modest period of snowfall is indicated. Snowfall totals by Wednesday morning would be in the 5-10 inch range and temperatures could approach the 30-degree mark at the base while remaining in the 20's a bit higher. The primary, occluded and initial area of low pressure will be up over the St Lawrence Valley and is likely to help continue spinning its leftover moisture in our direction. If I had to guess, much of the snow will come from that initial thump Tuesday evening and night followed by a several hour break followed by some persistent light snow during the day Wednesday and an additional 2-4 inches of snow. This would yield a storm total of about 7-14.

When I spoke of the PNA in the first paragraph and its apparent plan to throw a big "negative" bash that will continue for the next two weeks, my concern involves the impact that will have on the holiday weekend for us . A negative PNA isn't entirely bad for Vermont and with the help of a few other variables, the pattern can still find a way to productive. This "-PNA" is particularly strong however and capable of overwhelming about everything else. We certainly will get a bit more help on the storm track Tuesday/Wednesday but appear more likely to get less help on the holiday weekend. This has the potential to be another strong weather system and an interesting one but unfortunately, not an especially cold one. There are still several different possible scenarios that remain in play but the spectrum of possibilities is certainly slanted toward at least some wet weather and a period of above freezing temperatures in the Saturday/Sunday time frame (Feb 16-17).

There is some good news however. The ensuing holiday week looks better as time moves on thanks largely to a strengthening area of blocking in the jet stream over Greenland. Any subsequent storm, beyond February 18th, is more likely to be a snowy one and more productive for us skiers.


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