Think Snow, Tweet Snow !!!

Wednesday, February 25, 2009

Car wash Friday, but more new snow is on the horizon along with an improved long range outlook

Temperatures will rise above the freezing mark for the first time in a week but we should avoid most of the precipitation Thursday with the exception of a little snow in the morning and perhaps a blanket of thick fog in the afternoon. Friday will be unavoidable I am sorry to say. Temperatures will climb into the 40's supported by a stiff southerly wind and the rain will arrive sometime during the midday hours. We could see a few hours of rather heavy rain but it will all be over quick enough late in the evening with precipitation ending as a bit of snow prior to Saturday morning's first tracks.

Split flow phasing and some big storm potential
Things then get rather complicated and a bit interesting as the weather pattern throws us a bit of a curveball. It really did look as if, with all teleconnections moving into the unfavorable category, that a stretch of mild weather and lack of snow could sustain for a week if not more. This no longer appears to be the case; instead the jet will remain split and will phase early next week causing a serious jet amplification and a major east coast storm. There are timing, phasing, tracking and intensity questions and the possibilities remain a bit vast. The ingredients, amazingly, are there for the taking. There is a southern branch storm, a feature left behind by Friday's rain event and a northern jet upper air kicker, the kind that can start a fire without lighter fluid. The cold air's hold on Vermont will remain a bit tenuous and the storm will need to track close enough to MRG to bring its moisture but not too close as to erode the cold. Phasing of a storm such as this can also be a very delicate process and small changes in the timing of seemingly inconsequential weather parameters can make a big difference. The event could bring precipitation, ideally snow, to MRG Sunday and provide a big time powder day Monday. Be prepared for some changes as the uncertainty barometer remains quite high.

A longer range which looks much improved
The possibility of new snow for early next week was actually discussed in the previous post but I had given a rather gloomy outlook when discussing the end of the first full week in March. This forecast now appears much improved for you winter weather enthusiasts. The NAO, which has turned positive, will not stay so for long. Within a week it will be negative again supported by the return of the same feature which ruled the throne for the the last half of February. The longer range ensembles have adjusted somewhat and have kept most of the mild weather in the plains and have suggested a more wintry scenario including more new snow for MRG between the 4th and 8th of March. This is a striking turnabout but a welcomed one for those of us that would like to see the deep bases preserved for few more weeks before the warmth of spring emerges. With the specifics remaining so clouded 4 days from now it would be silly for me to spell out details later next week but 1 or 2 powder days is very realistic.

3 comments:

Matt said...

Mmmm, rain. Vertical challenge on Friday is going to be interesting ;) Hopefully there will be new snow when I can walk/ski again!

Nancy said...

I appreciate the updates. You've been pretty darn accurate. THANK YOU!

Jim Jenkins said...

I'm an English teacher, and "Epicality" is now part of my vocabulary! Here's hoping for a powder day on Sunday.