Small slab avalanches and afternoon warming are the concerns in today’s transitional springtime snowpack. Steep and sun affected southern facing terrain will have melting surface snow avalanches that could take you off your feet and into undesirable places. Evaluate recently deposited bright white slabs and slopes over 35 degrees in steepness as temperatures rise.
Wind drifted slabs formed from Sunday’s 3 inches have increased in overall stability, but may become reactive during afternoon warm up. These wind sculpted drifts still reside on eastern aspects in the middle and upper elevation slopes. Although relatively isolated in distribution, some of the wind transported pockets can be up to 6 inches deep.
We could see middle elevation temperatures this afternoon surpass 40F degrees with mostly clear skies. If prolonged sun exposure heats the surface snow long enough, small loose wet avalanches will increase in frequency. You could encounter loose sluffs in steep terrain over 35 degrees, especially in the afternoon hours on south and east aspects. A refreeze of the surface snow did occur overnight but was relatively superficial, with temperatures remaining in the upper 20s and low 30s Farenheit.
We have not seen new accumulations since Monday morning, which left behind 3 inches of snow in the middle and upper elevations. Wind transported snow has remained in sheltered terrain as isolated pockets of bright white snow that contrasts the surrounding gray. The characteristics of the recent snow is vulnerable to rapid warming and is therefore rolled into today’s avalanche hazard. Avoiding recent snow in steep terrain is the best way to steer clear of the danger.
Yesterday around 1:30pm, a small human-triggered wet slab avalanche occurred in The Lip. The slab propagated around 20 feet wide and connected to the southern flank of the larger D2 avalanche from March 31st. The crown depth was around 6 inches deep and in true slab form broke above the skier in steep terrain.
Falling ice is a concern on the rise as water undermines both the snowpack and structure of large ice columns. Witnessing a car-sized chunk of ice careening down towards you can be a horrific site that most would like to avoid. Stay out from under vertical water ice, especially in the Lunch Rocks area. This is one of the places to just avoid during this time of year.
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