Avalanche Forecast

High

Storm slabs have produced many size 1 to 2 avalanches in recent days, including numerous human-triggered slabs in the top 30 cm and larger natural avalanches in alpine terrain.

Large natural and artificially triggered persistent slab avalanches to size 3 were reported most recently on Saturday.

Expect continued storm slab activity on Monday. Persistent slab avalanches will become increasingly likely as temperatures warm this week.

Continued snowfall over the day Monday will bring storm totals into the range of 50 to 70 cm.

Several weak layers in the snowpack are currently concerns for triggering persistent slab avalanches:

• Facets/surface hoar/crust from early March buried 50 to 80 cm deep,

• Facets/surface hoar/crust from mid-February buried 70 to 100 cm deep, and

• Facets/surface hoar/crust from late January buried 100 to 150+ cm deep.

This complex snowpack combined with dynamic weather makes travel in avalanche terrain dangerous.

Sunday night

15 to 30 cm of snow, turning to rain below 1600 m. 40 km/h southwest ridgetop wind. Treeline temperature 0 °C. Freezing level rising to 2000 m.

Monday

10 to 20 cm of snow, rain below 1500 m. 30 to 40 km/h southwest ridgetop winds. Treeline temperature +2 °C. Freezing level 2000 m, rising to 2400 m.

Tuesday

5 to 10 mm of rain overnight then clearing skies in the afternoon. 20 km/h southwest ridgetop wind. Treeline temperature +6 °C. Freezing level 2700 m.

Wednesday

Sunny. 20 to 30 km/h southeast ridgetop wind. Treeline temperature +10 °C. Freezing level 3200 m.

More details can be found in the Mountain Weather Forecast.

• Avoid avalanche terrain during periods of heavy loading from new snow, wind, or rain.
• Be aware of the potential for large avalanches due to buried weak layers.
• Only the most simple non-avalanche terrain with no overhead hazard is appropriate at this time.