Saturday, December 27, 2014

Holiday Update - The Longer Version

Time for a long version and a bit more detail on what should be an interesting upcoming period across interior New England. We are finally coming to the end of a stretch of relative warmth. Fortunately, it wasn't record warmth but it came at an inopportune time and we are in need of some replenishment. I can't promise any of that in the short term I am sorry to say but we will see a return to winter-like temps following just about a tenth of an inch of rain Saturday night or early Sunday. It will then turn chilly with temperatures well below freezing through pretty much all of the upcoming New Years week. With the exception of a few flurries here and there, it will also be precipitation free.

Although arctic air will make a very profound descent on North America this week, it's continued presence across the U.S. beyond the 2nd across much of the U.S. including New England will not go unchallenged. The jet stream in the Pacific will remain relatively loose for a time, and we will have the support of some high latitude blocking which is expected to start in the Yukon and retrograde more to the Bering Sea. Let it be known that I would certainly prefer any high latitude blocking as opposed to none, but the position of this particular block in the jet stream will be west of a perfectly ideal location. Arctic air will thus have to contend with a upper ridge over the Southeast U.S. which will invariably want to push milder temperatures up the Eastern Seaboard.

There are nothing wrong with such challenges I will point out. This is how storms get churned up and often how very good periods of snowfall can occur across interior New England but it's always a close call and sometimes we end up with rain or ice. This is the very scenario that confronts us on or around the time of January 3rd, which will be the day, or close to the day when our next significant precipitation-producer arrives. The initial low pressure center is likely to pass to the west of New England but we could see a couple of things in spite of this. 1) We could see the storm transfer it's energy to the coast and save the region from another partial meltdown. 2) We could an extended period of overrunning snow before any change to sleet or ice or the dreaded rain. 3) We could still see the track of this storm shift south and east a bit more yielding a much more favorable result for the Vermont high country.

I think this will be a ongoing battle through around the middle of January. Cold weather fighting it out with an occasional mild push of air. Each of these air mass clashes though should bring the chance for a storm and some wintry precipitation to the region. It's hard to fathom this particular pattern lingering too long into January. A ridge across the southeast U.S. is not something that is typically very prevalent during any kind of El Nino, even a weak one. It will be interesting to see how this all evolves, but given the presence of arctic air, I would surprised if we end up with little or nothing to show for all this by January 15th.

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