The cooler temperatures are helping lock in the buried sun crusts, but increased winds with new snow have formed small wind slabs in the alpine that are worth paying attention to in steep terrain.
An intense cold front on Monday afternoon brought some new snow and increased Northerly winds. These inputs have formed small wind slabs in the alpine that could be triggered in steep terrain.
This crust facet layer down 20 to 40cm on steep slopes at treeline and above has produced several natural and skier triggered avalanches over the last few days. Diminishing solar inputs and cooling has decreased the sensitivity of these slabs.
Cooler temperatures are arriving following the passage of an intense cold front on Monday afternoon. Moderate northerly winds in the alpine with treeline temperatures steady near -15 C are expected on Tuesday. A mix of sun and cloud with no significant snow is forecast.
5-15 cm of new snow over a sun crust on steep solar aspects that exists up to about 2600 m. Northerly winds forming new wind slabs in alpine terrain. February 16 sun crust down 30-50 cm on steep southerly aspects. January 30 facet or sun crust interface is down 60-90 cm. Lower snowpack is well settled. Typical shallow areas remain faceted.
One cornice failure that triggered a size 2.5 slab avalanche was observed in the Rampart area near Sunshine in the last 48 hrs and a cornice failure near Crowfoot Glades was also observed. Ski cutting produced some small wind slabs at local ski areas. A couple slabs on steep solar slopes were observed Sunday with daytime heating.
