We've been in the Pass since Sunday on a guide training course. Groups have
been in the field on Monday (McGill Shoulder, McGill Pass, Grizzly Shoulder),
Wednesday (McGill Pass, Glacier Crest, Little Sifton) and Thursday
(Illecillewaet Glacier, Asulkan and Bonney Trees).
The week started with poor visibility, heavy snowfalls and an avalanche cycle
from the storm that has been affecting the Selkirks nearly continuously since
Christmas. Avalanches were up to size 3.5 and being triggered naturally, with
explosive control work and by skiers.
Snowpack depth at treeline is about 2 m. There is about 35 cm of low density
recent storm snow atop another 70 cm of well settled storm snow that has fallen
since Christmas. This all lies on a rain crust formed at Christmas and the
November crust near the ground. At the lower elevations we have been in there
are weaknesses within the upper part of the storm snow but that snow is so soft
that there is no slab. We haven't found instabilities around the Christmas or
November crusts.
We've been skiing below and at treeline and snow stability feels pretty good
there. It seems the large avalanche paths in the alpine are the concern due to
greater storm snow amounts and wind loading and weaker bonds at the deeply
buried crusts. Visibility was a bit better today and we could see into the
alpine. Natural avalanche activity has tapered off the last day or so and with
light winds at ridgetop and cool temps we felt OK about sneaking through the
runouts of the large avalanche paths. We still have low confidence with alpine
areas and any lower elevation areas threatened by large terrain above. There
were large avalanches triggered by large explosives to the west of the Rogers
Pass area today.
We started rating the avalanche danger at High in the alpine, High at treeline
and Considerable below treeline. Today we rated it Considerable, Moderate and
Low.
Mark Klassen
Dwayne Congdon
Colin Zacharias
Mountain Guides
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