Avalanche Forecast

A stalled offshore low continues to push bands of warm air, wind and precipitation our way in the upcoming days with clearing mid-week. 

Sunday night: Snow flurries, 5 to 10 cm, moderate to strong southwest wind and alpine low temperatures -8C with freezing level 800 m.  

Monday: Snow flurries, 10 to 15 cm, light south ridge wind gusting moderate and alpine high temperatures around -9C with freezing level 1400 m.

Tuesday: Snow flurries, 10 to 20 cm, moderate southwest wind gusting strong and alpine high temperatures around -6C.

Wednesday: A mix of sun and clouds with isolated flurries, light southwest wind gusting moderate and alpine high temperatures around -12C.

No new avalanches were reported from recent days, however we expect deteriorating conditions will make avalanches likely on Monday. This MIN from Friday reports that recent 10-15 cm is sluffing easily and is great evidence of how slippery the surface hoar layer/crust/facet layer is and how reactive it might become as slab properties develop in the snowpack.  

The deeper surface hoar layer from early January (buried 50-110 cm) was reactive 2-weeks ago in the North Blue River valley and continues to show up in test pits.   

Forecast snow overnight and into Monday contribute an additional 10-20 cm of dense snow with moderate to strong south west winds. This adds to the 10 cm reported in southern areas by Sunday afternoon, with less reported to the north. Up to 40 cm will now cover a recent and widespread known weak surface hoar / crust layer from the drought. Below 1600 m, 40-65 cm of snow is settling above a decomposing melt freeze crust.  

A weak of layer of surface hoar and crust from early January is 50-110 cm deep and tapers above 1700 m. This layer was last reactive almost 2 weeks ago (Jan 16) in the south of the region near Valemount. It is most suspect in sheltered, open slopes at and below treeline. Deeper in the snowpack, a couple of older persistent weak layers may still be identifiable from late and early December, consisting of surface hoar and a crust with faceted snow and buried anywhere from 70-150 cm deep. Deeper layers may wake up with heavy snow fall and warm temperatures.

• Back off if you encounter whumpfing, hollow sounds, or shooting cracks.
• Storm snow and wind is forming touchy slabs. Use caution in lee areas in the alpine and treeline.
• Watch for newly formed and reactive wind slabs as you transition into wind affected terrain.
• Carefully assess open slopes and convex rolls where buried surface hoar may be preserved.