[MCR] Powder Creek Southern Purcells

[Public Mountain Conditions Report]

March 1st -8th Powder Creek lodge


Lila Orr and I guided the past week at Powder Creek lodge in the Southern
Purcells across from Kaslo.  Overall we had excellent conditions and recent
warmth did not affect the snow until March 7. The week saw 90cm of snow
falling with gradually warming temps and settled to 55cm. Travel was
challenging due to deep trail breaking for the past 2 days but the powder
was deep and plentiful.  We were able to ski steep trees to 40 degrees but
only very limited alpine terrain.  The week started with -25 deg temps at
TL and ended with slightly above 0 deg temps.  We had light to moderate
west and south-west winds all week that created windslab on lee aspects at
treeline and above and built cornices.  The weather and poor visibility
limited us to skiing mostly at treeline and below. We dug profiles on North
and South aspects at tree line and found the Feb 10-Jan 28th layer to be
100-140cm down.  This layer was un-reactive to compression tests, but still
reacting suddenly to deep tap tests.  This lead us to avoid slopes with
shallow areas where we thought this layer could be reactive and avoid
exposure to overhead hazard during times of snowfall and warming.   Our
suspicions were confirmed on March 5th when we were traveling on a ridge
with shallow snow and we remotely triggered a size 2.5 avalanche below us
from 20m away.  The slide initiated in on a steep adjacent lee (SE) aspect
that had significant loading from the winds.  The crown was 150m wide, ran
150m long and was 160cm thick at its deepest point and 20cm deep at its
shallowest.  This was a good reminder that this layer is still a concern in
the right place.  Although visibility was limited we saw evidence of a
natural avalanche cycle out of steep lee and cross loaded features, and as
the skies cleared we were able to see the crown but not all of a suspected
sz 3 on a steep south alpine face at 2450m, we presently suspect the Jan
28/Feb 10 layer to be the culprit but can not confirm.  We also had one
natural cornice failure on a steep SE face that triggered sz 2.5 slab just
beside the crown of the remote avalanche.  The warmth that occurred  March 7
th created 5cm of moist snow on all aspects to 2100m.  The recent storm
snow is well settled and bonding to the Feb 28th interface.  Have fun and
stay safe.



Judson Wright ACMG ASG


Lila Orr ACMG SG
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