Avalanche Forecast
Regions: Flathead, Lizard, Lizard-Flathead.
Stick to mellow, simple terrain.
Avoid terrain that is being visibly wind loaded and don't linger on or under steep, sunny slopes.
Confidence
Moderate
Avalanche Summary
Wed: Explosives avalanche control produced numerous small to large (up to size 2) storm slab avalanches in north through east facing alpine terrain. Similar naturally triggered avalanches were also reported. Additionally, our field team reported numerous small dry loose avalanches out of steep slopes facing the sun.
Looking forward: Avalanches on buried weak layers may be difficult to trigger, but if one is triggered, it is likely to be large and destructive.
Snowpack Summary
Up to 25 cm of recent snow is settling on a widespread melt-freeze crust that exists on all sun-affected slopes, and as high as 1700 m on shaded slopes.
A weak layer of preserved surface hoar or facets from late January is buried 80 to 130 cm. This weak layer remains a concern where there is no thick, supportive crust under the recent snow.
The lower snowpack is generally well-settled and strong.
Weather Summary
Thursday Night
Clear. 10 to 15 km/h west ridgetop wind. Freezing level falling to valley bottom. Treeline low -7 °C.
Friday
Sunny. 15 to 25 km/h west or southwest ridgetop wind. Freezing level rising to 1700 m through the day. Treeline high -1 °C.
Saturday
Partly cloudy. 25 to 35 km/h southwest ridgetop wind. Freezing level falling to valley bottom overnight, rising to 1800 m through the day.
Sunday
Partly cloudy. 25 to 35 km/h southwest ridgetop wind. Freezing level around 1900 m.
More details can be found in the Mountain Weather Forecast.
Terrain and Travel Advice
- Be aware of the potential for large avalanches due to buried weak layers.
- Pay attention to the wind; once it starts to blow, sensitive wind slabs are likely to form.
- A moist or wet snow surface, pinwheeling, and natural avalanches are all indicators of a weakening snowpack.
- Avalanche activity is unlikely when a thick melt-freeze crust is present on the snow surface.
Avalanche Problems
Wind Slabs
15 to 25 cm of snow that fell Tuesday night into Wednesday morning may now be getting formed into reactive wind slabs below ridgecrests and in cross loaded gullies.
Aspects: North, North East, East, South East, North West.
Elevations: Alpine, Treeline.
Likelihood: Likely
Expected Size: 1 - 2.5
Persistent Slabs
A persistent weak layer is buried 80 to 130 cm. This layer remains a concern where there is no thick, supportive crust under the recent snow.
Aspects: All aspects.
Elevations: Alpine, Treeline.
Likelihood: Possible
Expected Size: 1.5 - 3
Loose Wet
With spring sun and freezing levels rising to 1700 m, wet loose avalanches will be most likely where there is significant loose snow over the crust, especially on steep slopes.
Aspects: East, South East, South, South West, West.
Elevations: Treeline, Below Treeline.
Likelihood: Possible
Expected Size: 1 - 2