Tuesday, December 27, 2016

Quick hitting storm to dump 6-12 inches Thursday Night into early Friday

We couldn't escape Christmas holiday period without 40-degree temperatures and rain. This makes 6 straight years with a thaw that have impacted the mountain within 3 days of Christmas Day. Yet in spite of the mild interlude, the weather is proving to be more productive during the good patterns and more resilient during the bad ones. We had been concerned that a "part II" of this warm looking week might impact the mountain in the Thursday/Friday time frame but it now looks to be exclusively snow and one of the better events of the season so far.

There were questions relating to the availability and viability of subtropical or southern branch moisture in the jet stream. The European model was hell-bent on suggesting this would be a key driver of this potential storm. It has taken several days for the American GFS model to hop aboard this train, but it finally has (somewhat), and we finally have some solid consensus for a decent winter storm. In the absence of Super Nino 2016, the European model has reasserted itself as the more reliable model in the 4-7 day time frame and is likely to again provide us with the needed clues that we have relied on so heavily over the years to make decisions on when to ski and perhaps when to find creative excuses to not work. In this case hopefully the upcoming holiday provides the needed excuse.

Snow showers Tuesday night into early Wednesday will re-whiten the mountain with a fluffy inch or two of accumulation. Wednesday and most of Thursday will otherwise be seasonable days with temperatures remaining just below the freezing mark during the day and in the teens during the night. Our storm approaches later Thursday as an elongated area of low pressure stretching from central Ontario south toward the mid-atlantic states. The southern part of this low pressure area will have the moisture and this will allow the storm to refocus its energy on the Atlantic Coast and deepen rapidly as it reaches the New England coastline Thursday night and early Friday. The radar won't appear to impressive most of Thursday but precipitation should enhance and Vermont will be under a decent area of snowfall Thursday night. Snow may begin to taper off by the ski day Friday but 6-12 inches should be on the ground and all of it should be of the powdery variety.

Cold weather and blustery conditions prevail for the remaining part of Friday along with some flurries. Temperatures will fall to about 10 Saturday morning and clouds should keep readings in the 20's Saturday. A clipper system is also expected to impact the region during the later part of Saturday (New Years Eve) and provide the mountain with another few inches of snow late New Years Eve. 

The longer range forecast has some good news in that the Arctic Oscillation or (AO) will attain a negative sign. This means that jet stream blocking at the Northern Hemisphere's highest latitudes will be more blocked. The persistently negative PNA however will continue to be the unwanted guest and appears to want to cause more trouble in the first full week of January. The cold will retreat after Jan 2 and we could have another mild scourge and some rain/ice around the time of January 3rd. The negative AO and loosening Pacific Jet should play a more prominent role after this occurs and a more positive outlook should emerge after January 4th or so.

1 comment:

billski said...

Thanks blogman.... I hear the same blowtorch-dump-blowtorch anthem as last year. Well, once is nota trend. I'll be sacrificing virgins to Ullr today.