Professional Observation

Observation Details

Signs of Unstable Snow

Key Points

Digging out this morning ended up being quite the mission, but I ended up getting out for a quick walk about in the Mill city area to get an idea of how things are stacking up from this latest storm. I kept it mellow and avoided being on or under slopes greater then 30° but I still managed to find many signs of instability.

• Surface instabilities are largely being driven by the wind today.
• I triggered several small and relatively shallow wind slabs in exposed areas below tree line. All the pockets I knocked loose today were 6-12” deep with wind condensed slabs around 4f-4f+. I would consider them sensitive and one of them I triggered remotely while approaching the test slope from adjacent terrain.
• I also initiated several shooting cracks within the storm snow on several gentle rollovers. The largest of which was about about 50’ in length and produced multiple cracks.
• Winds were ripping today and there is ample evidence of wind transport below treeline even in relatively protected areas.
• Snowfall totals seem to average about 30” with favorable terrain features holding deeper deposits and some windward areas stripped to the ground. I would describe the new snow as relatively dense. For reference the snow study plot at the base of mammoth is reporting 29” storm total with over 3.5” of snow water equivalent. That’s a lot of water packed into the snow.
• I expected to be in full trench warfare today, but ski pen was reasonable, however as soon as I got off my skies I sank to my chest. Deep snow immersion does not seem out of the realm of possibilities.