Avalanche Forecast
Issued: Mar 1st, 2020 8:06AM
The alpine rating is Persistent Slabs and Storm Slabs.
, the treeline rating is , and the below treeline rating is Known problems includeSlopes with previous heavy skier traffic or avalanche activity may not be as reactive on the February 22nd PWL. Don't get lured into larger terrain just because you ski cut a few small slopes and nothing happened.
Summary
Weather Forecast
A weak ridge of high pressure will give sunny periods and isolated flurries today. Treeline temps will reach a high of of -10 C and ridge wind will remain light from the West.
A system hitting the South Coast later this afternoon will bring strong wind, snow and rising temps to the area early this week. We could see up to 40cm by Wednesday morning.
Snowpack Summary
20cm of new snow came with strong SW winds yesterday and overloaded the February 22nd Persistent Weak Layer in many locations. This PWL is now buried 60+cm, and consists of 3-7mm surface hoar on all aspects up to 2450m and a crust on solar aspects. No other layers are currently active in the mid and lower snowpack.
Avalanche Summary
Avalanche control Saturday morning produced numerous large to very large avalanches (up to size 3.5) in the highway corridor.
Several natural avalanches occurred Friday night. Large avalanches (up to size 3) ran to valley bottom.
Numerous reports of skiers triggering small-large persistent slab avalanches (on the February 22nd layer) this week.
Confidence
Problems
Persistent Slabs
Surface hoar buried on February 22nd is now a persistent weak layer down 60+cm. The surface hoar overlies a thick crust on solar aspects. This layer was active yesterday and remains susceptible to human triggering.
- Minimize exposure to steep, planar slopes.
- Use conservative route selection, choose moderate angled and supported terrain with low consequence.
Aspects: All aspects.
Elevations: All elevations.
Likelihood
Expected Size
Storm Slabs
20+cm in the last 48hrs has formed fresh storm slab. The storm slab, where triggered, may step down to the Feb 22nd surface hoar layer.
- Use caution in lee areas. Recent wind loading has created fresh slabs.
- 934
Aspects: All aspects.
Elevations: Alpine, Treeline.
Likelihood
Expected Size
Valid until: Mar 2nd, 2020 8:00AM