Avalanche Forecast
Issued: Feb 18th, 2023 4:00PM
The alpine rating is , the treeline rating is , and the below treeline rating is Known problems include Storm Slabs and Deep Persistent Slabs.
jsmith,
Avalanche Canada
Forecast heavy snow and wind Saturday night and into Sunday will build touchy storm slabs. Large, natural avalanches are expected at all elevations.
Avoid all avalanche terrain during periods of heavy loading from new snow or wind.
Summary
Confidence
Moderate
Avalanche Summary
Forecast heavy snow and wind on Sunday will build reactive storm slabs. Large, natural avalanches are expected at all elevations.
Naturally triggered storm slabs were reported at treeline and above near Blue River on Friday.
Snowpack Summary
5-15 cm of new snow on Friday night brings recent snowfall totals to 40-50 cm. The recent snow is settling into storm slabs that will be most reactive where either wind has stiffened the snow or they overlie a layer of recently buried surface hoar.
Forecast heavy snow and wind on Sunday will build reactive storm slabs. Large, natural avalanches are expected at all elevations.
The mid-pack is showing signs of strengthening. A surface hoar layer down roughly 60 to 80 cm has not produced avalanches recently but can still be found in isolated terrain features specifically sheltered, treeline, and upper below treeline.
The lower snowpack is composed of large and weak facets from November located near the base of the snowpack. Additional load or step-down avalanches over the next few days may wake this layer up.
Weather Summary
Saturday night
Snow; 10-20 cm / Moderate west ridgetop wind / Low -8 °C / Freezing level valley bottom.
Sunday
Snow; 20-30 cm; another 5-10 cm Sunday night / Strong west ridgetop wind / High 0 °C / Freezing level 1400 m.
Monday
Mix of sun and cloud / Light northwest ridgetop wind / High of -5 °C / Freezing level valley bottom.
Tuesday
Mix of sun and cloud / Light east ridgetop wind / High of -13 °C / Freezing level valley bottom.
More details can be found in the Mountain Weather Forecast.
Terrain and Travel Advice
- Avoid all avalanche terrain during periods of heavy snowfall.
- Avoid exposure to overhead avalanche terrain, large avalanches may reach the end of run out zones.
- Storm slab size and sensitivity to triggering will likely increase through the day.
- Storm slabs in motion may step down to deeper layers resulting in large avalanches.
Problems
Storm Slabs
Forecast heavy snow and wind on Sunday will build touchy storm slabs. Large, natural avalanches are expected at all elevations.
Avoid all avalanche terrain during periods of heavy loading from new snow or wind.
Aspects: All aspects.
Elevations: All elevations.
Likelihood
Expected Size
Deep Persistent Slabs
A layer of large and weak facets sits near the base of the snowpack. This layer is most prominent in upper treeline and alpine elevations. Riders are most likely to trigger an avalanche on this layer in steep, shallow terrain. Your best defence is to stay diligent in choosing low-consequence terrain away from overhead exposure.
Aspects: All aspects.
Elevations: Alpine, Treeline.
Likelihood
Expected Size
Valid until: Feb 19th, 2023 4:00PM
