Overnight, storm snow and strong southwest winds will create very dangerous avalanche conditions for Tuesday. Avoid avalanche terrain during periods of heavy loading from new snow and wind.
Up to 25 cm of storm snow has settled with warm temperatures into a reactive storm slab over a variety of surfaces. Closely monitor how new snow is bonding to the surfaces below it.
Watch for rapid loading in the alpine and upper treeline as strong southwest winds redistribute storm snow into deep pockets on north and east slopes.
On Sunday explosives control saw only a few small dry loose avalanches to size one.
With +25 cm of snow expected tonight and strong winds, we expect backcountry users will see evidence of a natural storm slab avalanche cycle that occurred during the night as they move through the terrain tomorrow.
If you head out in the backcountry, let us know what you are seeing by submitting a report to the Mountain Information Network.
By Tuesday morning +25 cm of storm snow overlies a variety of surfaces including small pockets of wind slab on exposed south and west slopes, hard wind-affected surfaces in open areas, a sun crust on steep solar aspects, and facetted snow in sheltered areas.
The mid-snowpack is generally well-settled. The lower snowpack includes a layer of weak sugary crystals near the ground. These facets are slowly gaining strength and have not produced recent avalanche activity. We continue to track the layer and watch for any signs that it could wake up and produce very large avalanches.
Monday Night
Cloudy with mixed precipitation, 12-25 cm of new snow at upper elevations. Alpine temperatures reach a low of -6 °C. Ridge wind 50-70 km/h from the southwest. Freezing levels slowly lower from 1800 meters to valley bottom by morning.
Tuesday
Mainly cloud with isolated flurries, trace accumulation. Alpine temperatures reach a high of -4 °C. Ridge wind eases from 50 to 30 km/h from the southwest. Freezing level 1100 meters.
Wednesday
A mix of sun and cloud. Alpine temperatures reach a high of -3 °C. Ridge wind 10 km/h from the west increasing to 40 km/h in the afternoon. Freezing level 1300 meters.
Thursday
Mainly sunny. Alpine temperatures reach a high of -2 °C. Ridge wind east 10 km/h. Freezing levels rise to 1500 meters.
More details can be found in the Mountain Weather Forecast.
