Observation: Public

Observation Details

Signs of Unstable Snow

Observations

Quite a lot of rain today up to 3800', several inches of snow above. Dark, foggy, and cloudy except for a couple of brief 15 minute afternoon sun breaks. Winds 5-20 mph, temps in the mid twenties on the upper Mtn.

Snow up to the tree line was deep and soft but rain saturated.

The ridges between 4200 and 6800 feet (where I bailed out today) were soft and deep with 2-5' drifts caused by the boulders. The top 2-8" of snow (Friday?) formed a slab that was weakly adhered to the snow below. No shooting cracks, but blocks would pop out and slide when I passed by in snowshoes and the layer was obvious in a quick pit where it slid down when cut loose. I dug a deep pit at 5650 feet on a level area just above the seismograph. In this spot, the hard old snow that predates this 2-week old storm was 50 cm deep and easy to identify by its pumice coating. The whole snow layer was 110 cm deep with a hard 1 cm ice later at 60 cm and a 2 cm ice layer at 70 cm. There were no signs of weakness or instability and the easily shifted slab at the top was not present here. As I continued upward, that layer reappeared just 30 feet uphill.

Based on my observations, and the high variability in the snow depending on aspect, altitude, and geography, I chose to restrict my travel to the ridge crests near rocks and to avoid the wind loaded slopes, especially the east aspect of Monitor Ridge where the route travels between 7100 and 7700'.

I saw no avalanches or avalanche debris today. There were a few roller balls on steep slopes at 3700'. Two very small cornice failures at 5000' removed only a shallow layer on the slope below.