The present snow pack is the product of extended cooling on a shallow
early season snow pack. The primary culprit being a very weak faceted
layer of snow currently 60-100cm beneath the surface which is sitting on a
well developed crust from early December.
Looking at terrain with a conventional eye will only provide a partial
picture to the hazard that exists. The present threat goes well beyond the
familiar start zones and new snow instability people are typically looking
for when assessing hazard on the coast. Areas peppered with small trees,
boulders and bushes, many of which are buried just below the surface and
thus go unnoticed, represent the many countless micro super weak zones and
potential start zones in the present snow pack.
It is suspected that these super weak zones might be major players in
recently reported avalanche involvements over the past couple days. Be
aware that conventional avalanche control methods may expose none or only
part of the problem. It is important to realize that the protected tree
runs we conventional defer to when the hazard is high might posses the
same snowpack issues which are of concern on larger slopes. Differing to
lower angle terrain might be the first and best consideration to avoiding
the hazard. Avoid passing beneath large hazardous slopes and all features
steep and large enough to entrain enough snow to burry or injure a person.
It must be stressed above all else that there is still limited snow load
and the snow in many areas has as of yet little slab characteristic
overlaying the problem layer in the snowpack, expect it to come to life
again and again as we progress through the many storm cycles still to come
this winter.
Keith Reid
ACMG/IFMGA Mountain Guide
Whistler BC
keith@xxxxxxxxxx
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These observations and opinions are those of the person who submitted them. The
ACMG and its members take no responsibility for errors, omissions, or lapses in
continuity. Conditions differ greatly over time and space due to the variable
nature of mountain weather and terrain. Application of this information
provides no guarantee of increased safety. Do not use the Mountain Conditions
Report as the sole factor in planning trips or making decisions in the field.
Please check out http://acmg.ca/mcr for more information.
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