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Another week in the Valkyr Range, teaching an avalanche course.
As with all other areas there was an extensive avalanche cycle here in early January. Many lee slopes avalanched, especially east aspects. Avalanches were generally size 2 - 3, with some timber down. The most recent avalanche we've noted occurred on Jan 12.
Snowpack ranges from 140 cm at lower elevations to 240 cm in some alpine areas. Generally 200 cm at treeline. Coverage seems better than average for this time of year as the upper and mid pack is very well settled and carries well.
The December facets on the ground are about 70 cm thick and are 1F to 4F resistance. The midpack slab overlying them is 50-100cm thick and 1F to P resistance. We have had consistent moderate to hard compression test results on this layer, with a sudden collapse fracture character.
Temperatures have been incredibly warm, a maximum of +7 today, with a minimum of +2 last night. It doesn't look like it is going to freeze tonight either. Also incredibly, it doesn't seem like the warm temps have affected stability overly as test scores remain the same and no new avalanches have been noted. We'll see how long that lasts.
That said, we have little confidence in the snowpack and are sticking to small, supported terrain features to 35 degrees, low angle terrain and avoiding overhead hazard (especially cornices) and terrain traps. Experience has taught us that a persistent instability of this type is untrustworthy and has the potential to do unpredictable things. If something does go haywire it is going to be big and ugly. I don't want to get involved in anything like the avalanche that ran here recently, which tore up 100 year old trees by the roots.
We have found good, fast, low ski-pen turns on shaded aspects and low angled terrain elsewhere.
Mark Klassen Mountain Guide
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