[MCR] Northern Valhallas - 'Hare' Trigger Conditions

Subject: [MCR] Northern Valhallas - 'Hare' Trigger Conditions
Date: Fri, 12 Mar 2010 18:28:58 -0700
I have been tree skiing and tip toeing around the northern part of the range this week, as we got 30-40cms of cold smoke from Sunday nights cold front, then another 15-20cms yesterday, followed by 5-10cms and a spike of freezing levels to around 1800m today, with freezing levels already dropping now and continued snowfall.

Today we were able to trigger a size 3 at 2300m on north facing terrain from a ridge, around 200m wide, 30-70cm deep.  It was getting actively loaded by out moderate SW winds, and part of the slide was a repeater from 2 weeks ago.  Failure plane was the Feb 9 SH, but parts seemed to step down to the late January SH's.  It pulled back farther on the ridge then I have ever seen, but did not put us at risk.

Following that, we were skiing on 20 degree N to NW facing terrain at a similar elevation, and I was keeping the group far away from the run out of a short but steep north facing slope.  At a safe regroup in the trees, we scared a white rabbit and it proceeded to cross the steep slope I was concerned about.  As it got into the middle of the slope, it triggered a size 2, 100m wide, ~50-60cm deep on the Feb 9th SH, with a few spots stepping down to the late Jan SH sandwich. No sign of the bunny.

Obviously things are ripe, but the propagation around tree wells and micro ridges of these two slides is what really spooked me out.  Spicy times my friends, be safe!

Evan Stevens
Mountain Guide
Valhalla Mountain Touring
www.vmt.ca
evanstevens@xxxxxxxxx
evanstevens.blogspot.com




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