Avalanche Forecast
Issued: Apr 30th, 2021 4:00PM
The alpine rating is , the treeline rating is , and the below treeline rating is Known problems include Loose Wet, Wind Slabs and Cornices.
JMinifie,
Avalanche Canada
We've had rain at Fraser and freezing levels have been difficult to track in White Pass over the last 24hrs. Rain likely turns to snow at upper elevations and reactive Wind Slabs could be present in the high alpine.
Summary
Confidence
Weather Forecast
FRIDAY NIGHT: -2C, wind S/SW 20km/hr, cloudy, 3cm of sleet at valley bottom, 5cm snow in the Alpine. Freezing level 1500m
SATURDAY: low -2C high 2C, wind S/SW 10km/hr, broken skies, light precipitation ending around noon
SUNDAY: low -2C high 3C, wind variable 10km/hr, broken skies, trace precipitation
MONDAY: low -6C high 4C, wind N/NE 10km/hr, scattered clouds
Avalanche Summary
Wet snow now overlies firm surfaces. In some places, this wet snow is not sticking well. Check out this MIN for more details.
Wet loose avalanches up to size 2 have been observed throughout the region.
These types of avalanches will continue until we once again see below freezing temperatures overnight.
A big THANK YOU to all of you that provided us and fellow recreationists with observations this season. Please continue to do so if you head out!
Snowpack Summary
White Pass has now received over 24hrs of light rain and sleet at highway elevations. This has been accompanied by high freezing levels. This has contributed to the snowpack at lower elevations trending to isothermal and unsupportive. Above 1500m, the snowpack remains supportive to travel and dryer snow likely exists.
The lower snowpack in White Pass is deep for this time of year with no layers of concern. Areas further inland, such as the Wheaton Valley, may have a shallower and weaker snowpack.
Cornices are still very large. Recent cold temperatures have kept cornice failures to a minimum but they should always be treated with respect in the spring, especially when temperatures rise.
Terrain and Travel
- A moist or wet snow surface, pinwheeling and natural avalanches are all indicators of a weakening snowpack.
- Keep in mind that wet avalanches can be destructive due to their high density.
- Watch for newly formed and reactive wind slabs as you transition into wind affected terrain.
- Minimize your exposure time below cornices.
- Pay attention to cornices and give them a wide berth when traveling on or below ridges.
Problems
Loose Wet
Freezing levels are highly variable at this time. Assess temperatures and wetness of surface snow closely as you transition from Treeline to Alpine elevations.
Aspects: All aspects.
Elevations: Treeline.
Likelihood
Expected Size
Wind Slabs
Lower temperatures in the alpine may have allowed dryer snow to be blown into slabs. Use caution around wind loaded features.
Aspects: North, North East, East, South East, North West.
Elevations: Alpine.
Likelihood
Expected Size
Cornices
Aspects: North, North East, East, North West.
Elevations: Alpine.
Likelihood
Expected Size
Valid until: May 1st, 2021 2:00PM
