Avalanche Forecast
Issued: Dec 23rd, 2020 4:11PM
The alpine rating is , the treeline rating is , and the below treeline rating is Known problems include Wind Slabs, Loose Dry and Deep Persistent Slabs.
Jeff Andrews,
Sensitive wind slab continues to develop tree line and above all aspects. Dry loose problem will persist as well with continued wind input. Be wary of overhead exposure and conservative with terrain selection!
Summary
Weather Forecast
A mix of sun and cloud Thursday and Friday. Isolated flurries are possible on Saturday.
Ridgetop winds will remain in the light to moderate range from the west and southwest.
No significant precipitation is forecast this week..
Snowpack Summary
Up to 40cm settled storm snow from last week is being pushed around by previous northerly winds and present SW winds TL and above. The new snow sits upon a facet layer with isolated surface hoar sheltered areas TL and below. The midpack is generally supportive with a weaker base consisting of facets and depth hoar. Avg depth is 65-160cm.
Avalanche Summary
No Na activity noted on patrol south. Field team reporting whumphing and shooting cracks 2300m on southerly aspect - suspect sensitive wind slab up to 60cm deep continuing to develop on specific terrain features all aspects at treeline and above.
Confidence
Problems
Wind Slabs
Previous NW and present SW winds in the Alpine and open Tree line continue to develop wind slab all aspects. Caution as these freshly built wind slabs are reactive and waiting for a trigger.
- Be careful with reverse loaded pockets of wind slab at ridgeline.
- Be careful with wind loaded pockets, especially near ridge crests and roll-overs.
Aspects: All aspects.
Elevations: Alpine, Treeline.
Likelihood
Expected Size
Loose Dry
Numerous dry loose avalanches up to size 2 out of steep alpine terrain noted yesterday on Mt.Wilson, Heads up climbers, There is a lot of overhead above you at the moment.
- Be cautious of sluffing in steep terrain, particularly where the debris flows into terrain traps.
- Minimize exposure to terrain traps where the consequences of an avalanche could be serious.
Aspects: All aspects.
Elevations: Treeline, Below Treeline.
Likelihood
Expected Size
Deep Persistent Slabs
Be cautious of thick to thin snowpack areas being likely trigger locations. The wind slabs have the potential to step down to the weakness at the base of the snowpack.
- Use caution in thin snowpack areas.
- If triggered the wind slabs may step down to deeper layers resulting in large avalanches.
Aspects: All aspects.
Elevations: All elevations.
Likelihood
Expected Size
Valid until: Dec 24th, 2020 4:00PM
