Avalanche Forecast
Issued: Dec 20th, 2019 4:17PM
The alpine rating is , the treeline rating is , and the below treeline rating is Known problems include Storm Slabs, Wind Slabs and Deep Persistent Slabs.
Darren Vonk,
Parks Canada
Stay out of avalanche terrain as this storm tests our weak snowpack. Weeping wall & polar circus will be closed Saturday and Sunday due to avalanche control on the Icefields Parkway. Emergency road closures are possible depending on storm intensity.
Summary
Weather Forecast
Continued precipitation tonight and into tomorrow could see up to 30cm
Saturday: Periods of snow. Accumulation: 16 cm. Alpine temperature: High -3 C. Mostly light ridge wind occasionally gusting to 40 km/h. FL: 1700M
Sunday: A mix of sun and cloud. Precipitation: Nil. Alpine temperature: Low -13 C, High -9 C. Ridge wind light to 15 km/h. FL at VB
Snowpack Summary
10cm new over the last 6 hours, Light winds continue building variable strength wind slabs on lee and crossloaded features at or above treeline. Persistent interfaces layered through the snowpack that might wake as the up to as the 35cm's of new snow forecasted in the next 36 hours accumulates.
Avalanche Summary
No new avalanches observed today with poor visibility and a field trip to Parkers ridge area.
Confidence
Forecast snowfall amounts are uncertain
Problems
Storm Slabs
As new snow accumulates, Expect the hazard to increase.
- Minimize exposure during periods of heavy loading from new snow and wind.
- 892
Aspects: All aspects.
Elevations: All elevations.
Likelihood
Expected Size
Wind Slabs
Continued S-SW winds are creating wind slabs in NW to SE lee aspects. Sensitivity expected to be reactive in the immediate future and may wake deeper, weaker interfaces.
- Avoid all avalanche terrain during periods of heavy loading from new snow, wind, or rain.
- The recent snow may now be hiding windslabs that were easily visible before the snow fell.
Aspects: All aspects.
Elevations: Alpine, Treeline.
Likelihood
Expected Size
Deep Persistent Slabs
Triggering the windslab problem has potential to step down to this layer.
- If triggered the storm/wind slabs may step down to deeper layers resulting in large avalanches.
Aspects: All aspects.
Elevations: Alpine, Treeline.
Likelihood
Expected Size
Valid until: Dec 21st, 2019 4:00PM
