Vail & Summit County
AvalancheKreston Rohrig · Jan 17, 2020 · Vail & Summit County
Weather
Blustery when it was snowing. There were a few periods of intense snowfall throughout the day dropping snow at rates of S2-S5. Combined with a gusty west wind, conditions felt very stormy. There was a lull in the action before noon, with a second wave that ramped up around 1:30pm
Snowpack
We dug a quick pit below treeline on an east aspect to see how the recent storm snow is shaping up. The slab is still very soft (fist hard) and sits above weak snow (4 finger) from the middle of the snowpack to the ground. None of these layers were reactive in stability tests. More interesting was the new slab formation in drifted areas. This was a major concern today with the new snow and forecast for strong winds. Leeward, east-facing slopes were building soft slabs anywhere from a few inches to a foot in the areas we observed. On one test slope, we easily triggered a small pocket of wind-loaded snow that formed above an older wind-hardened layer. We didn't travel above treeline, but given the conditions, I'd bet there were similar slabs forming. Even at lower elevations, the 4-6 inches of new snow was drifting around, filling in old tracks and concave features.
Avalanche
I intentionally triggered a small wind-drifted pocket on a near-treeline leeward slope. The slope was small and not dangerous, so perfect as a test slope. The freshly formed slab was super soft and easy to trigger.