Faceting

[yuckster]

Seems like this has been an unusual year for the Northeast, with (as I have been worried about recently and the below seems to confirm) the snowpack apparently behaving quite a bit like a Continental snowpack due to our long cold snap and all the dry upslope snow we got this year.

Be careful out there.

Originally Posted by Brian Johnston, Snow Ranger

The Lip remains the outcast due to the pronounced weak layers I found hiding under hard slab. As mentioned yesterday, these slabs could be pretty difficult to trigger; however, if an avalanche did occur it would be a deep hard slab avalanche. The upper slab in the snowpack has benefited from solar gain over the past few days and it poses little threat of propagating. The only major concern is if the thicker and colder slabs under them were to be disturbed enough to collapse the weak layers underneath. I think it is likely that you could find these facet layers in other locations in the Headwall area. The Lip catches our attention more due to the consistency of the slab and terrain factors such as pitch and shape of the start zone. If you are into looking at snowpacks and weak layers it is a good time to get into Tuckerman Ravine. Overall we have a stable snowpack with a lot of facets scattered around. It is a good opportunity to poke around and see differences in the relationships of layers as the snowpack varies so much.

[PWDR8S]

Sounds like a great opportunity to check out the layers, etc! Def a twist considering we're a Maritime climate.

[davidhowland14]

this might be the future of NE given climate change and all that...not that bad a change, but we could use some more gnar early season

[yuckster]

I saw a Vermont snowpack referred to as a "temperate continental" snowpack in one snow-science paper:

http://www.easternsnow.org/proceedin...027_Taylor.pdf

I'm no snow-science geek so I don't know what to make of it, but this is interesting. Most of us here in the East assume that our snowpack is maritime and doesn't have the ticking timebomb problem. Maybe that's wrong.

[Affix Snow]

If it rips, it gonna go BIG.

[RR]

Originally Posted by Affix Snow

If it rips, it gonna go BIG.

I'm thinking that we knew there would be problems like that in early January due to weak bonding with the December ice cover....and now there's this other weak layer above that....

So I guess that after going big...there's still a hang-fire potential.

[surf88]

At least it is looking pretty tasty up there.
From 2/26

[PWDR8S]

Originally Posted by RR

I'm thinking that we knew there would be problems like that in early January due to weak bonding with the December ice cover....and now there's this other weak layer above that....

So I guess that after going big...there's still a hang-fire potential.

I remember we were discussin this very issue early in the season.... I remember mentioning to watch the base layers and what may develop due to it. I cannot seem to find the thread.

This is something we need to keep track of!

[tig]

There's weaks bridged by crusts:
http://www.flickr.com/photos/tig/388...7594532845255/

As the snowpack size increases with the valentines day snow and this storm the faceting should reverse and the sugar should start to go away some. Perhaps by spring, when we want it to, the facets would have mostly reversed. If not, we might be in for some nasty surprises as the snowpack melts and the upper slabs are not enough to support our weight..

[yuckster]

Before full-on melt becomes an issue I think we can expect a bombproof rain crust to develop at some point.

(There, I said it.)

[lacman]

Originally Posted by tig

As the snowpack size increases with the valentines day snow and this storm the faceting should reverse and the sugar should start to go away some. Perhaps by spring, when we want it to, the facets would have mostly reversed. If not, we might be in for some nasty surprises as the snowpack melts and the upper slabs are not enough to support our weight..

Originally Posted by yuckster

Before full-on melt becomes an issue I think we can expect a bombproof rain crust to develop at some point.

(There, I said it.)

Both rain and melting in the springtime will do a similar thing to the snowpack...give it free water. This then percolates down and eventually refreezes into a pretty solid mass of frozen corn. Any facets that get hit by free water will rapidly turn to wet snow grains, weak until refrozen. What isn't a good thing to see is a springtime rainstorm provide a lot of water that percolates down to an existing ice crust and then has nowhere to go. This lubes up the ice tremendously, and if the waterfall is running in the headwall we can see massive avalanches such as this one:


Notice all the rain runnels in the Lip, and how it pushed farther out to the side as it went down. The crown gives fresh meaning to "hucking the Lip"

Let's just hope for more and more snows like today and lots more slides to fill in the bottom of the ravine. I want to be able to ski right out over the Little Headwall this year without going through the bushes!

Happy snow day!
lm