Avalanche Forecast
Issued: Feb 5th, 2020 4:00PM
The alpine rating is , the treeline rating is , and the below treeline rating is Known problems include Wind Slabs, Deep Persistent Slabs and Persistent Slabs.
Stephen Holeczi,
Parks Canada
Coverage and ski quality is quite good right now. Newly formed wind slabs will be something to watch out for in the next few days, and the deeper weak layers are still capable of producing large avalanches if triggered.
Summary
Weather Forecast
Winds will start in the moderate to strong range but diminish over the day Thursday from the SW. 2000m temperatures around -8 and alpine temperatures decreasing to -16 over the day. Expect light flurries.Â
Snowpack Summary
30 to 70 cm of recent storm snow at higher elevations, with a rain crust up to 1800m. Wind slabs exist in the alpine and exposed areas at tree line. The Dec 31 layer of facets, surface hoar and sun crust is currently down 50-100cm. The deep persistent basal layer sits 20 to 40cm above the ground and is more developed in shallow snowpack areas.
Avalanche Summary
No avalanches reported or observed today. However, we are just coming off of a fairly substantial cycle from the last weekend which saw large avalanches up to size 3.5 running to valley bottoms.
Confidence
Due to the number and quality of field observations
Problems
Wind Slabs
Previous storm snow from this past week has been redistributed by increased SW winds over the past 2 days. These wind slabs could be quite thick in some spots and should be treated with caution, especially in alpine features.
- If triggered the wind slabs may step down to deeper layers resulting in large avalanches.
Aspects: North, North East, East, South East, North West.
Elevations: Alpine, Treeline.
Likelihood
Expected Size
Deep Persistent Slabs
Deep releases on the facets and depth hoar could be less likely but are hard to predict. Dealing with the uncertainty around this layer can be somewhat managed by avoiding large, committing terrain and areas with a thin snowpack.
- Minimize overhead exposure during periods of heavy loading from new snow, wind.
- Avoid shallow snowpack areas where triggering is more likely.
Aspects: All aspects.
Elevations: All elevations.
Likelihood
Expected Size
Persistent Slabs
This layer of surface hoar, facets and crusts is down 50 to 100cm and produces variable results, many in the hard range or no result.
- Dig down to find and test weak layers before committing to a line.
Aspects: All aspects.
Elevations: Treeline.
Likelihood
Expected Size
Valid until: Feb 6th, 2020 4:00PM
