Professional Observation

Observation Details

Signs of Unstable Snow

Key Points

We post-holed through the snowy sage to get to continuous snow cover near Bishop Bowl to watch the timing of the storm.

• When we left the car at 11:15 am it was snowing lightly with no accumulation. Winds were strong and variable. Any existing snow cover was around a foot deep and broken up by rock and sage. Surfaces were pencil hard windboard.
• We found continuous snow cover, and the persistent slab snow structure, at 9500 feet. We got repeatable propagation on the 12/1 interface – under the crust (see snow profile).
• By 12:10 pm it was snowing about a half-inch per hour. Winds were from the southwest and we started to notice some accumulation and fresh drifts a few inches deep.
• Standing in our snow pit at 9900 feet at 1:30 pm, it was snowing an inch per hour. Blowing snow was intense from southwest winds.
• By the time we where post-holing back down the moraine to Aspendell, at 2:30pm, it was snowing almost 2 inches per hour and blowing sideways. Rain/snow line was at 6800 feet.