Grand Mesa
SnowpackColin Mitchell · Mar 1, 2015 · Grand Mesa
Weather
Intermittent snow showers. Sun was visible behind thin clouds and made it feel warmer than it was. 18" Hst since Thursday, with 1.2" H20.
Snowpack
The snow from this week and our last storm has formed a slab 45-50 cm thick. The most recent snow is 4F hard, but the snow from last week has stiffened up to 1F. Below this were two layers of F hard facets, and three layers of buried SH. Beneath that was a 70 cm thick layer of P hard facets and DH rounding. Snowpack tests last Wednesday in this location were not producing results indicative of propagation. Today was a different story. 3 ECTs failed on the uppermost facet layer beneath the slab. ECTV, ECTP6, and ECT12. PSTs on this same layer scored PST 24/100 end, and PST 25/100 end. Additionally, during the 400m or so that I traveled off of the groomed trails, I experienced 6 collapses, several of them quite large, 40-60m in diameter. The attached photo shows the layering in the upper 75 cm of the snowpack quite well. There was plenty of evidence of prior wind-loading with 1-2 foot high drifts, and cornices forming on the edge of the cliffs. Low snow supply in the cliffs, and lots of small sluffs have kept the avalanche hazard manageable during this storm so far, but forecast heavy snow and winds will likely tip the balance here.