Warming surface snow below treeline and recent avalanche activity

Date of Observation: 03/29/2023
Name: Eric Murrow

Zone: Northwest Mountains
Route Description: Evans Basin on Mount Emmons and Kebler Pass/Ohio Pass corridor.

Observed avalanche activity: Yes
Avalanches: A few small loose avalanches from warming today. Two loose avalanches triggered slabs on east aspects. One older avalanche likely failed during Monday’s storm that initially failed in storm snow and then stepped down two more feet; this avalanche snapped on small tree in the runout (D2.5).
Weather: Increasing clouds in the morning that were mostly cloudy in the afternoon. Temps reached close to 40 degrees below treeline. Light winds at low elevations, no snow transport was observed above treeline in the areas I traveled.
Snowpack: I took a look at the impact of yesterday’s and today’s warming on the snowpack on the south half of the compass. In general, I found crusts 1.5 – 3 cm thick (up to 1.25 inchs). I did not find liquid water draining into the snowpack much below the surface. Crusts on some steep sunny slopes might be supportive to skis tomorrow, but I suspect slightly breakable. I observed several snowbike tracks on steep sunny below treeline slopes that did not produce avalanche activity.