I guided a group at Selkirk Lodge from January 21-30th, this is near Albert Canyon just East of Revelstoke and West of Rogers Pass. We received over 1 meter of snow during the
week and the skiing was characterized by what is known as champagne powder. We
had moderate temps all week with highs of -3 and lows of -15. Visibility was
limited but there were some breaks in the weather that allowed us some occasions to ski
mountaineer and ski above tree line.
The major concerns for the week were the incredible amount
of new snow load as well as the accompanying moderate to strong winds. We
witnessed strong to gale force winds in the Alpine coming from both the South
and North. This produced widespread wind
slabs and cross loading, both on lee aspects and as reverse loading at ridge
top, fall line ridge features and any wind exposed open areas. We expected this
to cause wind affected poor ski quality in open areas but of greater concern
to overload either the Dec 03 surface
hoar layer (down 130-180cm), the Jan 20 faceted layer down (60-80cm) or buried
wind slabs (down 60cm).
Surprisingly we had excellent skiing conditions despite the winds. Further more, these layers of concerns displayed good bonding,
mostly good compression and ski cutting results failing only on the steepest
most unsupported features as moderate to hard resistant planar/progressive compression
or skier controlled sloughs. We did see some limited avalanche activity (one size 3) from steep
unskiable alpine terrain as well as from ridge top wind loaded
features (up to sz 2), these had occurred in the height of the storm, but in
all we were very surprised to see a lack of a large natural cycle.
Perhaps the answer to this uncharacteristic stability is
that the snow came down at moderate temps and the wind always subsided near the
end of each storm pulse. The amount of snow, the moderate temps and the
gentling of the storms seemed to promote bonding of the snowpack through
sintering and settlement. The fact of
the matter however is that there are layers of concern and wind slabs that undoubtedly still pose a potential threat in
specific terrain features and which could cause a very large avalanche.
It is easy to let ones guard down in such conditions it was prudent to remain cautious of the following terrain features:
1.
On Jan 24 on a ridge top lee loaded feature and from the safety of a tree and having seen a side profile of where the cornice was rooted, I carefully
approached the cornice the size of say two compact cars. I gingerly reached out and stomped on the
cornice about 10 - 15 cm back from its root. Surprisingly it failed immediately, propagating 15 meters on either side of me as well as
pulling back 5 – 15 centimeters from the edge throughout its length. This a significant occurrence since I applied a very
light load, it needed only a hair trigger, it propagated and pulled back. It left me quite surprised that it had not failed in the past strong winds
and I think there are many large cornices which are sitting time bombs right
now in the Selkirks. In this case the cornice was over a very low angled slope so it did not trigger much of an avalanche below. We avoided terrain threatened by cornices.
2.
In the Alpine, on two occasions I came across a
thick and dense hard slab sitting over up to 60 cm of depth hoar/facets combo that produced very easy test results as well as whumpfing.
We avoided and any shallow, wind loaded alpine feature that were large and steep or unsupported.
3.
At Treeline and below, we did notice that convex
unsupported features would occasionally fail within the storm snow (20-40 down). My feeling is that it is entirely
possible for a large open treeline or below treeline convex/unsupported feature
to be overloaded right now and only need the right trigger to set it off. We
avoided any large unsupported features and always ski cut the top of smaller features.
All in all it was an epic week of blower powder and following the above mentioned cautions, we skied
steep, well supported open and treed slopes in the alpine, treeline and
especially great tree skiing below.
Enjoy the amazing snow in the Selkirks!
Eric Dumerac- Professional Mountain Guide
✆ 403-609-1564
Mountain Skills Academy