Tuesday, February 12, 2013

Models downplaying big weekend snow but we at least get some and then more next week

It's crunch time in the ski season and it would be nice to follow up on last weekend's big winter storm with some additional snows. The decent looking southern branch system tracking toward the Delmarva Wednesday will actually bring some wet snow to some areas already buried by last weekends snow but interior New England will stay dry and be forced to wait for the big weekend jet amplification for any real action. The recent cycle of model runs has generally downplayed the big storm potential this weekend and is suggesting a briefer period of light snow and a light accumulation ahead of another surge of Arctic cold. The Canadian model released Tuesday afternoon still produced a "doozy" of a winter storm (borrowing the phrase from "Groundhog Day") for the weekend with a whole gammit of winter weather including some big snow for the high country. Although the Canadian solution seems less likely, it still illustrates the potential in such a setup. When a jet amplification of this magnitude occurs, the atmosphere becomes a powder keg along the Atlantic Coast and it is very easy to churn up something big. At the very least though, we should be able to produce a few inches Friday night into early Saturday. The weekend appears to be a chilly one with temperatures in the teens by day and below zero at least Sunday and Monday mornings.

Flurries and snow showers will accompany the colder weather over the weekend even if we don't get a big snow. The holiday Monday however appears to be on the dry side, dominated by a cold high pressure center. Temperatures will then moderate Tuesday into Wednesday but the focus will be on what appears to be a relatively organized weather system which will move out of the Rockies late this weekend and approach MRG by Tuesday. The playing field will consist of a decaying area of cold and a storm which may track up the St Lawrence Valley. This is a recipe for a warm push but there will be serious resistance and a healthy overrunning zone across New England. As a result, I am of the opinion, for now that this system will mostly be a snow producer in spite of some model guidance suggesting otherwise. The SCWB will keep a close eye on this since I know many plan on heading to the mountains during the upcoming holiday week. A second even more organized system should crush the eastern Rockies with snow during the middle of next week and then proceed to cross the country with some serious energy and moisture. By this point, there will be plenty of available cold air and the critical question will probably relate to whether snow from this storm will reach interior New England or whether we stay dry.

The pattern during the holiday week and persisting through the duration of the month should be an active one. It is as I mentioned a battle between a negative North Atlantic Oscillation and a tightened Pacific Jet. The ensembles are indicating that the dreaded mid-latitude Pacific Ocean upper ridge (the evil empire)  will not be a total party pooper and will position itself closer to Hawaii as opposed to the eastern Pacific. What I am hoping as an end result consists of limited cold and plenty of winter storms crossing the country.

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