Avalanche Forecast

Moderate

• We are uncertain about how quickly persistent slabs are gaining strength.

A few large (up to size 3) natural persistent slab avalanches have occurred in recent days. One size 3 may have been remotely triggered. These large avalanches have occurred on northwest through east-facing slopes in the alpine.

Roughly 5 cm of new snow has buried a strong, supportive crust that is expected on the surface on all aspects at treeline and on all but north-facing terrain in the alpine.

Below treeline, a full overnight refreeze may not occur, resulting in a thin, weak, breakable crust. Wind-affected surfaces are likely in north-facing alpine terrain.

A thick crust with weak faceted snow is buried roughly 100 to 200 cm deep and continues to produce large, surprising avalanches.

Sunday Night
Partly cloudy. 1 to 2 cm of mixed precipitation at treeline. 40 km/h west ridgetop wind. Treeline temperature 0 °C. Freezing level 1400 m.

Monday
Mostly cloudy. 2 to 4 cm of snow. 50 km/h southwest ridgetop wind. Treeline temperature -3 °C. Freezing level 1100 m.

Tuesday
Mostly cloudy. 10 cm of snow. 40 km/h south ridgetop wind. Treeline temperature -3 °C. Freezing level 1000 m.

Wednesday
Mix of sun and clouds. 1 to 3 cm of snow. 20 km/h north ridgetop wind. Treeline temperature -4 °C.

More details can be found in the Mountain Weather Forecast.

• Avoid steep, rocky, and wind-affected areas where triggering slabs is more likely.
• Use extra caution around cornices: they are large, fragile, and can trigger slabs on slopes below.
• Be aware of the potential for large avalanches due to buried weak layers.
• Be careful as you transition into wind-affected terrain.