Northwest Inland

Forecast strong southwest winds may trigger large natural avalanches in the alpine on Thursday.

Choose simple, low angle terrain, and avoid overhead hazards.

• Make conservative terrain choices and avoid overhead hazard.
• Watch for signs of instability like whumpfing, hollow sounds, shooting cracks, or recent avalanches.
• Be aware of the potential for larger than expected storm slabs due to buried surface hoar.
• Use small, low consequence slopes to test the bond of the new snow.
• Storm slabs in motion may step down to deeper layers resulting in large avalanches.

Moderate

• We are uncertain about how the snowpack will react to the forecast weather.

A widespread natural storm slab avalanche cycle occurred over the last few days on all aspects/elevations. Storm slabs up to size 2 were reported at treeline and below.

There have been very limited alpine observations, but we suspect numerous natural very large avalanches (size 3.5 or larger) have occurred.

Forecast strong southwest winds may trigger large natural avalanches in the alpine on Thursday.

Recent snowfall amounts have varied from 65 to 150 cm, with the highest amounts being in the south of the region. The recent snow and strong southwest winds have formed reactive storm slabs overlying a weak layer of surface hoar and/or facets. This weak layer will make large storm slabs more likely to trigger.

There are multiple persistent weak layers consisting of crust/facets or surface hoar in the top 200 cm of the snowpack.

Wednesday Night
Mostly cloudy. 3 to 10 cm of snow. 50 km/h southwest ridgetop wind. Treeline temperature -4 °C.

Thursday
Mix of sun and clouds. 50 km/h southwest ridgetop wind. Treeline temperature -5 °C.

Friday
Mostly cloudy. 0 to 5 cm of snow. 20 km/h southwest ridgetop wind. Treeline temperature -6 °C.

Saturday
Mostly sunny. 30 km/h southwest ridgetop wind. Treeline temperature -7 °C.

More details can be found in the Mountain Weather Forecast.