Touring up Magnum today we experienced the following:
Obvious signs of instability
-No recent avalanches in the past 48 hrs
-No shooting cracks
-One large collapse at 2500 feet, approx. 75 x 75 feet
Surface Observations
Current problems:
-Wide variation in slab hardness and thickness above treeline, ranging from no
slab in wind scoured areas to 60cm/24″ pencil hard wind slabs
-Below treeline we have not seen enough cohesive snow to have a slab avalanche
problem
Future problems:
-Wide variety of weak surface snow; surface hoar up to treeline, near surface
facets above treeline. It seems that the winds of 12/19 knocked over and blew
around any surface hoar that was previously standing up above treeline
Pit results
-2500 feet NNW aspect, 32 degree slope
-PST 15/100 end
-ECTP 11
-ECTV
-CTV
-Layer of Greatest Concern: facets 50 cm below the surface
(see video and photos)
With no reported avalanche activity in the last 5 days we headed out today
looking for areas with suspect snow. We struck gold on Magnum! Other tours in
recent days have shown signs of improving stability. But, given our
understanding of the generally poor snowpack structure and the high variability
of the slabs, we aimed to get a better grasp of the problem (Persistent Slabs).
We’ll be paying attention to these areas in the coming days and monitoring the
snow surface in order to anticipate how these layers will behave once they have
a new slab sitting on top of them.