Avalanche Forecast
Issued: Mar 5th, 2023 4:00PM
The alpine rating is , the treeline rating is , and the below treeline rating is Known problems include Wind Slabs and Persistent Slabs.
rgoddard,
Avalanche Canada
Variable winds have created reactive wind slabs on all aspects and could be at elevations lower than expected.
Seek out sheltered terrain for the best riding.
Summary
Confidence
Moderate
Avalanche Summary
On Saturday, a natural cornice fall trigged the slope below it. This occurred below treeline and was on a west aspect. The aspect and elevation are fairly atypical but representative of the moderate easterly winds we have been experiencing. Make sure to watch out for wind affect on all aspects and elevations.
Check out Friday's North Shore Snowpack Update for a picture of our atypical snowpack setup.
Snowpack Summary
Easterly winds have started to transport the 100 to 130 cm of snow that fell last week. This snow was mostly dry and cold. Warming temperatures have increased the consolidation of the upper snowpack and may promote slab development. If the sun pokes out, it could do the same since it is starting to pack a punch this time of year.
This recent snow sits on a layer of concern made up of a crust with facets. It appears to be gaining strength, but this is a layer to watch out for.
The mid and lower snowpack is well-settled, strong, and consolidated.
Snowpack depths are over 300 cm.
Weather Summary
Sunday Night
Cloudy with clear periods, trace accumulation, winds southeast 15 to 25 km/h, freezing level to 1200 m.
Monday
A mix of sun and cloud, trace accumulation, winds southeast 25 to 35 km/h, freezing level climbing to 1100 m by end of the day.
Tuesday
Cloudy with possible late-day sunny breaks, 10 cm accumulation, winds southeast 30 km/h gusting to 40, freezing level 500 to 1000 m.
Wednesday
Mostly cloudy, 10 to 15 cm accumulation over the 24-hour period, winds southeast 25 km/h gusting to 40, freezing level to 900 m.
More details can be found in the Mountain Weather Forecast.
Terrain and Travel Advice
- Be carefull around freshly wind loaded features.
- Loose avalanches may start small but they can grow and push you into dangerous terrain.
- Fresh snow rests on a problematic persistent slab, don't let good riding lure you into complacency.
- Caution around slopes that are exposed to cornices overhead.
- Recent wind has varied in direction so watch for wind slabs on all aspects.
Problems
Wind Slabs
Easterly winds may have developed wind slabs on aspects that do not normally see wind slabs. Winds from the southwest that accompanied last week's storms may also have produced reactive wind slabs. Expect wind slabs on all aspects in exposed terrain.
Reactivity is expected to persist for longer than is typical, particularly in areas where slabs are sitting on a weak layer of facets and/or a crust.
Aspects: All aspects.
Elevations: Alpine, Treeline.
Likelihood
Expected Size
Persistent Slabs
This past week's snow is covering a crust facet combo layer. If triggered this weak layer could produce a large-scale avalanche.
Here is a great video on this layer's development.
Aspects: All aspects.
Elevations: All elevations.
Likelihood
Expected Size
Valid until: Mar 6th, 2023 4:00PM
