It's going to be a sunny and cool day! Wind slabs that were formed by strong to extreme wind from the south, west and northwest on Sunday might still be reactive to human triggers.
Strong south and westerly wind formed wind slabs on Sunday. Wind slabs will be found below ridge crests and in lee terrain features. The strong wind might have built slabs farther down slope than expected.
Monday night: Clear with cloudy periods, moderate northeast wind, alpine low -12 °C, freezing level at valley bottom.
Tuesday: Sunny, moderate northeast wind, alpine high -9 °C, freezing level at valley bottom.
Wednesday: Mix of sun and clouds, trace of new snow, strong southwest wind, alpine high -8 °C, freezing level at valley bottom.
Thursday: Mainly cloudy, up to 4 cm snow, extreme south wind, alpine high -7 °C, freezing level at valley bottom.
Skiers were surprised by wind slab avalanches on north and northeast aspects in the White Pass area on Friday. The slabs were about 20 cm thick and the avalanches reached up to size 2. Slabs were still reactive to skier traffic on Saturday.
30-40 cm of recent snow are sitting on old firm surfaces. Strong wind from the south and west transported the snow and formed wind slabs on Sunday. The bond between the recent snow and the old firm surfaces was reactive to skier traffic in the last few days. On steep, south aspects at treeline and below, there is potential for the existence of a thin sun crust.
The lower snowpack is well bridged by the layers above, and it is unlikely that avalanches will be triggered on weak, sugary crystals near the ground at this time.
