[MCR] Rogers Pass

Subject: [MCR] Rogers Pass
Date: Thu, 19 Jan 2006 22:06:27 -0800
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