Avalanche Forecast

Moderate - Uncertainty is due to the timing, track, & intensity of the incoming weather system. Forecast snowfall amounts are uncertain.

Continued snow through the Christmas holidays. Expect some heavier snowfall amounts Thursday with the passing cold front.  

Wednesday Night: 5- 10 cm of new snow accompanied by strong ridgetop wind from the southwest. Alpine temperatures near -5 and freezing levels 900 m.

Thursday: New snow throughout the day, with 10-25 cm accumulation. Strong ridgetop wind from the southwest. Alpine temperatures near -2 and freezing levels 1100 m. 

Friday: Flurries with new snow 5-10 cm with moderate to strong southwest wind. Alpine temperatures near -5 and freezing levels valley bottom.

Saturday: Mostly cloudy with some flurries 5-10 cm. Gusty ridgetop winds from the South and temperatures dropping to -12 with freezing levels valley bottom. 

On Wednesday, the South Rockies field team reported several wind slabs that appeared to have slid on the early December crust and up to size 2. 

With the new snow and strong wind, fresh and reactive storm and wind slabs will be reactive through the forecast period. 

New snow and wind will likely build reactive storm slabs through Friday. This new snow will bury older wind slabs from last weekend's storm and in exposed areas, strong to extreme winds may strip many areas back down to the early December curst and create deposits of hard wind slab in lees. 

Below the new snow exists a well-consolidated upper snowpack which overlies a substantial crust that formed in early December. This crust is approximately 50-90 cm below the surface, 20 cm thick on average, and is present across all aspects to at least 2400 m. A layer of weak facets (sugary snow) has been reported above this crust. Snowpack tests are generally showing hard results on this interface, however, areas, where avalanches have recently failed on this crust, continue to be problematic once reloaded with new snow. 

Below 2300 m, several early-season crusts make up the lower snowpack. Snowpack depths range from 80-150 cm at treeline elevations and taper quickly below 1900m.

• Watch for fresh storm slabs building throughout the day.
• Avoid all avalanche terrain during periods of heavy loading from new snow and wind.
• Be aware of the potential for large avalanches due to the presence of a persistent slab.