Avalanche Forecast
Issued: Dec 13th, 2020 4:00PM
The alpine rating is , the treeline rating is , and the below treeline rating is Known problems include Wind Slabs.
JSmith,
Avalanche Canada
Small wind slabs may remain reactive to human triggers in isolated locations. Use caution when transitioning into wind affected terrain.
Summary
Confidence
Weather Forecast
SUNDAY NIGHT: Cloudy / Moderate, northwest ridgetop wind / alpine low temperature -15 / Freezing level valley bottom.
MONDAY: Cloudy / Light, northwest ridgetop wind / alpine high temperature -10 / Freezing level valley bottom.
TUESDAY: Snow; 3-5 cm. / Strong, southwest ridgetop wind / alpine high temperature -8 / Freezing level valley bottom.
WEDNESDAY: Cloudy with isolated flurries; 0-3 cm. / Strong, west ridgetop wind / alpine high temperature -6 / Freezing level valley bottom.
Avalanche Summary
No new avalanches were reported in this region on Saturday.
Data in this region is very sparse. Please submit your observations to the Mountain Information Network.
Snowpack Summary
Strong northerly winds formed wind slabs on lee features at treeline and above.
10- 20 cm of recent snow fell at upper elevations while the rest of the precipitation came in as rain or freezing rain. Recent reports suggest that the freezing rain occurred from 1800m to 2000m “ish” with rain at lower elevations which may have destroyed the surface hoar at 2000m and below. All elevations are now hosting a burley crust under the new snow. Up high, stiff wind slab exists on leeward slopes where the new snow deposits into deeper drifts, especially where the new snow sits above this recent rain/freezing rain crust, or the older melt-freeze crust found on solar aspects.
Digging deeper in the snowpack two crusts exist from November. One down approximately 30 cm, just below the old surface hoar, and the other sits deeper (down 70-90 cm) and is widespread up to 2500 m. The deeper crust seems to be bridged by a well-consolidated mid-pack in most areas. These crusts have shown no recent reactivity in snowpack testing but remain on our radar moving forward.
The snowpack is generally thin, wind hammered, variable in wind-scoured areas, and tapers rapidly at lower elevations. Snowpack depths at sheltered upper treeline elevations are nearing 100 cm and beginning to exceed the threshold for avalanches.
Terrain and Travel
- Watch for newly formed and reactive wind slabs as you transition into wind affected terrain.
- Be careful with wind loaded pockets, especially near ridge crests and roll-overs.
- Recent wind has varied in direction so watch for wind slabs on all aspects.
- Avoid areas where the snow feels stiff and/or slabby.
Problems
Wind Slabs
Isolated pockets of wind slabs could be reactive to human triggers.
Aspects: All aspects.
Elevations: Alpine.
Likelihood
Expected Size
Valid until: Dec 14th, 2020 4:00PM
