South Rockies

Persistent slabs remain possible to human trigger at treeline and above, especially in areas without a supportive crust above the weak layer.

Moderate

• We are confident that there are persistent slabs in the snowpack, but uncertain about how likely they are to trigger.
• We are uncertain due to a limited number of field observations.

On Monday, numerous explosive triggered wind slabs up to size 2 were reported on primarily north/east aspects at treeline and above.

Up to 30 cm of recent snow in the north of the region, 5 to 15 cm elsewhere. Strong southwest winds have redistributed this snow at treeline and above.

Rain has formed a supportive crust to 1500 m near Golden, rising to 2100 m further south. Where this crust is absent or unsupportive, concern remains for a persistent weak layer of surface hoar or crust buried 50 to 70 cm deep, and up to 100 cm down in deeper snowpacks such as the Dogtooth Range.

In shallow snowpack areas, depth hoar (large facets) can be found near the bottom of the snowpack.

Tuesday Night
Mostly cloudy. 0 to 5 cm of snow. 50 km/h southwest ridgetop wind. Treeline temperature -11 °C.

Wednesday
Mostly cloudy. 0 to 3 cm of snow, then another 10 to 15 cm overnight. 50 km/h west ridgetop wind. Treeline temperature -11 °C.

Thursday
Mostly cloudy. 3 to 5 cm of snow. 50 km/h west ridgetop wind. Treeline temperature -8 °C.

Friday
Mix of sun and clouds. 20 km/h west ridgetop wind. Treeline temperature -10 °C.

More details can be found in the Mountain Weather Forecast.

• Be aware of the potential for large avalanches due to buried surface hoar.
• Watch for signs of instability like whumpfing, hollow sounds, shooting cracks, or recent avalanches.
• Watch for newly formed and reactive wind slabs as you transition into wind-affected terrain.
• If triggered, wind slabs may step down to deeper layers, causing larger avalanches.
• Avalanche activity is unlikely when a thick melt-freeze crust is present on the snow surface.