Even in a good year, La Nina can hang Vermont right on the edge. With this storm, like many others it is touch and go all the way to the finish line. Some you win and some you don't. With this one it looks like we come out on top. The storm in question will not intensify the way I thought it might a day or two ago. As a result it will be able to transfer its energy to the coast quicker thus stopping the flow of warm air at key levels of the lower troposphere.
I've looked at some of the latest data from the high resolution models which are shining some light on specifics. Precipitation will arrive in the form of snow and begin as early as noon Friday with temperatures within a few degrees of freezing. The snow could become moderate to fairly heavy for a time during the afternoon and accumulate a few inches before lift closing time. It could make for a decent afternoon of skiing if you can sneak one in. This initial wave of snow will actually taper to flurries during the evening. At this time, temperatures a few thousand feet up might still exceed the freezing mark opening the door for the possibility of some freezing drizzle or light sleet. At the surface however, temperatures will hover between 25 and 29 for much of the evening and the overnight. Around midnight, the second batch of good upward motion associated with the storm will arrive and the threat of freezing rain/sleet will be gone (I don't think we really see too much of that). Snow should re-commence and could become heavy in the pre-dawn hours. In the end, the heaviest snow will only persist for a few hours but it will be enough to blanket MRG with 6-12 inches of relatively dense powder. The critical temperatures for powdery vs wet snow is about 28 or 29 degrees (depending on a few variables) and base temperatures will be right there. Temps at mid-mountain and at the summit will support powder all the way through. Even after the heaviest snow is completed, lingering instability will allow terrain induced snow to persist through much of Saturday. It will be mostly light to occasionally moderate snow and enough for an additional 2-4 inches.
And for those heading up from those southern locales let me say this. Driving to Killington or Okemo may not get it done. Much better chance for a period of sleet or freezing rain in central and southern Vermont. If your going to make the drive, make it to MRG, the best place to be on a powder day without question !!!
The Rocky Mountains will actually spit out two additional weather systems over the next week. The first moves into the Great Lakes and up the St Lawrence Valley Monday night. This is a system that lacks moisture and will lose some of its dynamic support as it presses east which will prove to be a blessing since its track would suggest maybe a rain event if it were stronger. In the end, this has the makings of a light accumulation of snow if at all. The second system will generate a lot of discussion and will arrive Wednesday as a much more potent storm with plenty of moisture. Again, Vermont should be right on the edge and could see an icy mix, maybe some rain or maybe a big winter storm. I will call it the "Leap Year" storm since its arrival will be on Feb 29. We could go back to our 2012 ways and flame out on this event but we have the chance to score big so stay tuned.