Resurrecting a dead thread here, but I figured I'd let anyone who is interested that I finally got enough snow to try this out.
It's funny, it seems that the combination of my proposing the "lager in snow bank" idea and buying snowshoes guaranteed that the winter of 2012 would bring the lowest snowfall ever. It was nuts, I never had enough snow (maybe 4 inches) to use my snowshoes, didn't use my snowblower after the first week of January, it barely got cold enough in my wine cellar to ferment a lager all winter, and I played my first round of golf on March 12.
This year seemed like the same thing, until "blizzard 2013" hit last week. I happened to have a pilsner fermenting anyway, and I had a spot with enough snow down (maybe 15 inches of snowfall, 36 inches after snowblower piles) to try lagering it in the snow.
I put 3 gallons in a BB, have the airlock filled with vodka so it should stay liquid, put a freezer bag loosely over the airlock and taped in place, then put the whole thing in a large heavyweight black garbage bag, folded over and taped closed. I dug a hole in the snow deep enough that it would have buried my 4 year old (had to have someone finish digging) and now that fermenter is buried treasure.
The 10 day forecast suggests that the snow will stick around for a little bit (daily highs ranging from 30 to 40, overnight lows in the high 20s consistently) with a little more snow maybe tossed in there. So I might get 3 weeks of lagering in there before the fermenter sees the light of day.
I'll be back with a taste test between lagering in the snow and the fridge (the other 2 gallons are lagering in a Mr Beer) in a few weeks. I figure ill see how long lagering in the snow lasts and as long as it is a semi reasonable amount of time (say 3 weeks) I will bottle both halves of the batch at the same time. If this outdoor lagering trick only lasts a few days .... I'll figure it out then.
Pretty jacked up that I was playing golf by mid March last year and am depending on the snow sticking around this year. I prefer last year.