Avalanche Forecast

Friday night: Clear / light northwest winds / alpine low temperature -15

Saturday: Sunny with patchy cloud / light west winds / alpine high temperature -12

Sunday: Mix of sun and cloud, isolated flurries / light variable winds / alpine high temperature -13

Monday: Cloudy with sunny breaks / light variable winds / alpine high temperature -12

There have been no recent avalanche observations in the region. 

On Wednesday, operators in neighboring Glacier National Park reported several large (size 2-2.5) wind slabs releasing naturally on a variety of aspects (north, east, and south). Two natural cornice failures were reported in Glacier National Park on Wednesday releasing above north-facing slopes. This MIN report from north of the region in Hope Creek reports human-triggered wind slab activity on Wednesday.

This MIN report from the Quartz zone from last week shows a reactive layer of Jan 11th surface hoar on north-facing slopes near treeline. It may be possible to trigger this layer in isolated areas where the surface hoar has been preserved. 

Following last week's storm, we received reports of avalanches reaching size 3 in the central part of the region, lending support to the idea that some larger releases may have involved more deeply buried persistent weak layers. Check out this MIN report from Mt McKay. Although avalanche activity on these layers from early December and November has been isolated, the possibility exists for large triggers to reactivate these deeper instabilities. 

Recent winds have scoured snow surfaces, loaded cornices, and formed stiff wind slabs in alpine and upper treeline areas. A new sun crust may be forming on steep solar aspects. Clear skies and cold temperatures are encouraging surface hoar growth and surface faceting.

30-60 cm of snow buried a weak of layer of surface hoar from Jan 11th. This persistent weak layer is most suspect in sheltered, open slopes at treeline. This layer has produced sudden results in snowpack tests at treeline elevations in areas near KHMR and warrants snowpack investigation if you're travelling in the north of the region.

Two deeper layers of surface hoar from December 13th and December 7th may still be found down 100-150 cm. The Dec 7th weak layer consists of a combination of decomposing surface hoar with a crust and faceted snow. Avalanche activity on these persistent weak layers has dwindled in the last week, with snowpack tests results trending to resistant and unreactive. 

The lower snowpack is characterized by a notable rain crust from early November that is surrounded by a weak layer of sugary facets. It may still be possible to trigger with large loads in steep, shallow, rocky areas with a thin to thick snowpack.

• Be careful with wind slabs, especially in steep, unsupported and/or convex terrain features.
• Avoid shallow, rocky areas where the snowpack transitions from thick to thin.
• If triggered, wind slabs avalanches may step down to deeper layers resulting in larger avalanches.