Avalanche Forecast

Good

Tonight and Wednesday: A ridge of high pressure is bringing cold and clear conditions. Strong winds from the E-NE are forecasted, mainly clear skies and temperatures around -19 C.Thursday: The ridge remains dominant bringing similar conditions except moderate winds from the NE and slightly warmer temperatures (-11 C).Friday: Similar conditions with lighter winds.

Several skier triggered slab avalanches size 1 to 2 were reported yesterday around Nelson area. These would have been triggered in windslabs overlying the end of January surface hoar on N and NW facing slopes.

Recent and ongoing strong Easterly winds created windslabs on lee and cross-loaded features in the alpine and at treeline. The windslabs, in wind exposed areas or loose dry snow in sheltered areas, overlies well developed and widespread surface hoar or a crust on solar aspects.  This combination has resulted in recent skier triggered avalanches up to size 2. Natural activity is less likely now but these 10-30 cm thick windslabs could still be triggered under the weight of a skier. Below this layer, you'll likely find about 10cm of faceted snow over older surface hoar and old, unreactive wind slabs. Mid-January’s prolonged warm temperatures have formed a strong and supportive midpack. Deeper persistent layers have become unlikely to trigger, although large and destructive avalanches are still possible in isolated terrain with the right input such as a cornice fall or a heavy load over a thin spot in steep terrain.