A layer of warm air between 2000m and 2500m may combine to loosen the snowpack and the cornices on ridges. Keep your eyes open for increasing avalanche activity in the afternoon, and give cornices a wide berth.
Summary
Weather Forecast
Valley cloud with temperatures in the -5 range, and moderate SW winds. A chance of isolated flurries today, and tonight. An above freezing layer of air may bring temperatures up to 3 degrees from 2000m to 2500m today as well. Overnight the temperature drops to -9 and light snow can be expected into Friday.
Snowpack Summary
Surface snow is facetting with cold temps. Recent tests indicate that the interface down ~30cm between the new and old settled snow will fail with moderate force but is resistant to move. The Nov. crust is down 160cm collapses with a hard force in snowpack tests but has yet to produce avalanches. Snowpack depths are below average.
Avalanche Summary
Recent activity has been confined to steep unskiable terrain. Small, loose avalanches also ran during this period from steep solar aspects, before clouds moved in reducing the solar effects. Skiers report sluffing of the top 20cm on steep slopes.
Confidence
Problems
Loose Dry
The loose upper snow sluffs easily on very steep slopes. So far, these have been small (size 1) skier and solar triggered loose avalanches. On large steep slopes, particularly gully features, these may gain mass and become larger.
Be aware of party members below you that may be exposed to your sluffs.Avoid travelling on ledges and cliffs where sluffing may have severe consequences.
Aspects: All aspects.
Elevations: All elevations.
Likelihood
Expected Size
Cornices
Warm air at treeline and above combined with sun may cause cornices to weaken and fall. Be cautious near or under cornices.
Extra caution needed around cornices with current conditions.Avoid steep slopes below cornices.
Aspects: All aspects.
Elevations: Alpine, Treeline.
Likelihood
Expected Size
Valid until: Jan 4th, 2013 8:00AM
