Cooler, cloudy weather with light precipitation is expected on Sunday. Freezing levels will rise to around treeline.
Avalanche hazard will be lower in the morning, and will depend on the quality of the overnight refreeze and the amount of daytime warming. Start and finish early.
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An 80 cm thick midpack slab sits over a weaker, facetted base. On most slopes, recent sun crusts and a buried March 27 rain crust cap this slab, adding strength as long as it is frozen. We suspect it would take a large trigger, like a cornice or intense solar input, to trigger these deeper layers.
Monitor the overnight crust refreeze, daytime temperatures and solar inputs. The likelihood of loose wet avalanches will increase with warmer temperatures as the day progresses. Start and finish your tour early to avoid this problem.
On Sunday, cloud cover will increase, accompanied by light precipitation as a low-pressure system moves into the forecast region. Treeline temperatures will be between -1°C and +3°C with light SW winds.
Solar heating contributed to increased loose wet avalanche activity on E-S-W aspects on Saturday, beginning on steep solar aspects by noon. By mid afternoon, we were seeing the crust break down which resulted in a loose wet avalanche cycle to size 2.
We also received reports of recent cornice releases in the afternoon over the past couple of days.
Surface crusts exist to ridgetops in the morning on solar aspects, and on all aspects at treeline and below. The top 10-20 cm of snow on solar aspects was getting moist by noon on Saturday.
North alpine slopes hold 5-15 cm of dry snow over firm surfaces. The March 27 crust is 30-70 cm deep and extends to about 2500 m on North slopes, reaching the ridgetop on solar aspects.
Below the settled mid-pack, weak facets and depth hoar remain.
