Dry sluffs are occurring in steep terrain. This is important for people who are skiing steep couloirs. Today we responded to one party who got knocked down a steep gully by a sluff avalanche from above. The snow is so dry it is sluffing easily.
Weather Forecast
Wednesday's weather will be the same as Tuesday's - overcast skies, no new snow, light winds and temps from -2 to -10. On Thursday an Arctic front crosses the area and we can expect up to 5cm of new snow. In the wake of the front, temps will fall and it looks like north winds and -20 for Friday. Check our weather stations for current conditions.
Snowpack Summary
The snowpack is well settled with few weaknesses. Sun crusts exist on steep S/SW aspects and large surface hoar is forming below 2000m. Isolated wind slabs exist in the alpine. Below 2000m, the Dec 3 layer of surface hoar and facets remains visible down 20-50 cm but is currently dormant. Thin areas are faceting out and weakening.
Avalanche Summary
No new slab avalanches today, but a party triggered a size 1.5 sluff avalanche in a steep gully. This relatively small avalanche gained speed, hit a party below and they tumbled down the couloir. A good example of a small avalanche having a big impact due to the committing nature of the terrain.
Confidence
Problems
Wind Slabs
Wind Slab avalanches are the release of a cohesive layer of snow (a slab) formed by the wind. Wind typically transports snow from the upwind sides of terrain features and deposits snow on the downwind side. Wind slabs are often smooth and rounded and sometimes sound hollow, and can range from soft to hard. Wind slabs that form over a persistent weak layer (surface hoar, depth hoar, or near-surface facets) may be termed Persistent Slabs or may develop into Persistent Slabs.