Avalanche Forecast

Good

Monday: heavy snowfall continuing overnight into Tuesday - strong to extreme southwest winds - freezing level at 1300m Tuesday: continued heavy snowfall - strong southwest winds decreasing throughout the day- freezing level at 1100m Wednesday: a mix of sun and cloud as a clearing trend develops - light and variable winds - freezing level at 900m

Numerous natural and human-triggered slabs to size 2.5 were observed in the Duffey lake area over the last few days. The suspected sliding layer has consistently been the March 26th interface (see snowpack observations). On Face Mountain in the Railroad Pass area 2 sledders triggered a size 2 avalanche while riding the slope at the same time. The slide was 60m wide and 50cm deep and was most likely triggered on the March 26 layer. The sledders escaped without injury. With weather forecast for Monday, expect widespread windslab and storm slab avalanche activity with serious potential to involve the deeper March 26th layer.

40-70cm of snow that fell over the past few days now overlies an interface that was buried on March 26. This interface consists of a crust that exists on all aspects and elevations except north facing slopes at treeline and above where small surface hoar (5mm) may be found in sheltered areas. This week's snowfall has been accompanied by consistently moderate and at times gusty southerly winds forming windslabs in lee locations. The bonds between the new snow and the March interface have been weak, especially in locations where the surface hoar is present. At lower elevations, the consistent high freezing levels have kept the new snow moist and heavy. The deep, persistent early February layers linger in the snowpack and remain a concern with heavy triggers and rapid loading. Cornices are huge, and have continued to grow with this weather pattern.