Friday, January 28, 2011

Most of weekend clipper system to go south, big storm possible next week

To be perfectly frank, I was a little down watching another foot of snow fall in New York city. Don't get me wrong, when I live in NYC, which i did for several years, I enjoyed a big snow more than anyone. I don't live there now though and I would much rather here about snow, thundersnow and three inch per hour snow somewhere in the vicinity of the single chair as opposed to the big metros. The snow in the big cities this year has caught many prognosticators by surprise. Conventional wisdom, as mentioned many times on the blog would have the general storm track in a La Nina year much farther north. Its also a little frustrating that most of the moisture with the incoming clipper will track south of the region while more or less fall apart. The mountain will get sporadic light snow or flurries and this will amount to 1-3 inches during the day Saturday. More flurries are likely Sunday but it won't amount to much.

A more "traditional" La Nina picture will emerge next week and I expect the mountain should do rather well powder-wise as a result. There was some strong evidence on the Euro Ensembles earlier this week of a southeast ridge manifestation and a storm to go along with it. This weather would gather healthy amounts of Gulf Moisture and travel up through the eastern Ohio Valley and eventually off the northeast coast. This would be a nice track for a general swath of 10-20 inch snows across the Green and White moutais in the Wednesday-Thursday time frame of next week after a very cold and dry start to the week Monday and Tuesday. The storm remains 5-6 days out and the trend this year has been for every storm to track farther south so lets not count our chickens. For now, it does look promising for a nice "powder" period late next week.

For the first time this year really, the collection of teleconnection indices which add to produce our "favorability index" will turn negative. The PNA had taken the lead in the recent weeks as a western ridge extending deep into the high latitudes helped to bring the recent surge of cold and keep the snow falling and the rain away (although recent days have been dry). The PNA is expected to go negative beginning next week as the above-mentioned western ridge shifts west off the Pacific Coast and both the AO and NAO are expected to remain positive. We have been overdue for this shift but the silver lining in all this news is that the ensembles have (all of them) continue to show a signal of below normal temps and a somewhat decisive signal I must admit. The coldest weather is shown to impact much of the eastern part of Canada (which has been amazingly warm so far this winter) and some of this cold is indicated to keep New England in the grips of some winter chill. If this shift in the weather pattern means nothing more than shifting the storm track slightly to the north than the bad news is actually good news. In reality though, the threat of ice or rain goes up in this type of set-up so we should be ready for almost anything.

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