Avalanche Forecast
Regions: Coquihalla, Harrison-Fraser, Manning, Skagit.
Accumulating snowfall and increased winds will raise the avalanche hazard throughout the day today.
Watch for building storm slabs and larger-than-normal deposits created by the wind.
Seek out sheltered low-angle riding.
Confidence
High
Avalanche Summary
In the last several days, no avalanche activity has been reported. This is expected to change drastically with incoming precipitation.
Last week, a skier accidental wind slab avalanche was reported on a south-facing slope at 1800 m. This avalanche was 70 cm deep and is suspected to have slid on the Jan melt-freeze crust. New snow on this layer could start producing more avalanches like this.
Please continue to post your reports and photos to the Mountain Information Network.
Snowpack Summary
Up to 50 to 70 cm of new snow may accumulate by the end of the day on Tuesday. At upper elevations, southwest winds have redistributed recent snow into fresh wind slabs. On southern aspects, recent snow overlies stiff wind slabs. A breakable crust may exist near the surface on steep solar aspects and at low elevations.
A melt-freeze crust formed in mid-January is now buried 50 to 80 cm deep. Weak, faceted crystals have been observed growing above it meaning it may pose a problem going forward. On the bright side, it is one of several crusts bridging other weak layers in the mid to lower snowpack, meaning that triggering deeper avalanches on them is unlikely.
Snowpack depths are significantly below seasonal averages for this time of year, 150 to 200 cm at treeline, tapering rapidly below 1500 m.
Weather Summary
Monday Night
Cloudy, up to 20 to 25 cm accumulation, winds southwest 40 km/h, treeline temperatures -4 C.
Tuesday
Cloudy, up to 30 cm accumulation for the Coquihalla, winds southwest 40 to 50 km/h, treeline temperatures -3 to -5 C.
Wednesday
Cloudy, 5 to 10 cm accumulation, wind southwest wind 15 to 30 km/h, treeline temperatures -6 C.
Thursday
Cloudy with possible sunny breaks, trace accumulation, winds south southwest 20 to 30, treeline temperatures -2 C.
More details can be found in the Mountain Weather Forecast.
Terrain and Travel Advice
- Watch for fresh storm slabs building throughout the day.
- Watch for changing conditions today, storm slabs may become increasingly reactive.
- Storm slabs in motion may step down to deeper layers resulting in large avalanches.
- Be carefull around freshly wind loaded features.
Avalanche Problems
Storm Slabs
A storm system that arrives Monday and will continue to bring snow on Tuesday will increase the chance of storm slab avalanches. Below around 1400 m this snow may be rain and it too will add load to the snow pack. Strong southerly winds that accompany this weather system will load pockets of areas with even more accumulation. Expect these wind slabs to be reactive as well.
Aspects: All aspects.
Elevations: All elevations.
Likelihood: Very Likely
Expected Size: 1 - 2