Avalanche Forecast
Issued: Mar 20th, 2022 4:00PM
The alpine rating is , the treeline rating is , and the below treeline rating is Known problems include Persistent Slabs and Wind Slabs.
wlewis,
Avalanche Canada
Danger ratings have dropped, but potential to trigger buried weak layers still exists in the central and southern Cariboos.
Expect avalanche danger to change as you travel through different aspects and elevations.
Summary
Confidence
Moderate - Uncertainty is due to the fact that persistent slabs are particularly difficult to forecast.
Weather Forecast
SUNDAY NIGHT: Increasing cloud with moderate southwest winds. Freezing levels drop to valley bottom. Scattered flurries.
MONDAY: Scattered flurries with mostly cloudy skies. Moderate southwest winds. Freezing levels reach 1700 m. Alpine high of +1
TUESDAY: Mostly cloudy with scattered flurries. Strong southwest winds. Freezing levels remain high, reaching 2200 m. Alpine highs around +4.
WEDNESDAY: 5-10 cm of snow forecast as freezing levels drop to 1500 m over the day. Moderate southwest winds. Alpine high of +2.Â
Avalanche Summary
Avalanche activity has been tapering off over the week, with natural activity observed on Thursday. On Wednesday large remotely triggered avalanches were reported on north and south aspects with impressive propagation.Â
On Saturday, a rider triggered a size 1.5 slab avalanche on a southeast facing treeline slope.
Small wet avalanches have been reported within the last 5 days, on all aspects below the freezing line and on sun affected slopes.Â
Snowpack Summary
Up to 70 cm of recent settling storm snow sits over a layer of weak surface hoar in sheltered and shaded terrain, and over a crust on south facing slopes. The new snow is bonding poorly to this old surface in some areas, producing large avalanches within the last 5 days, and reactive results on testing.Â
At higher elevations consistent southwest winds are creating deeper deposits on north through east facing features. Below 1500 m, moist snow or a melt-freeze crust likely exists from recent rain and warm temperatures.
The lower snowpack is generally well-settled and strong in most areas, with crust layers 50 to 100 cm deep.
Terrain and Travel
- Potential for wide propagation exists, fresh slabs may rest on surface hoar, facets and/or crust.
- Carefully assess open slopes and convex rolls where buried surface hoar may be preserved.
- Avoid freshly wind loaded features, especially near ridge crests, roll-overs and in steep terrain.
- Minimize exposure to sun-exposed slopes when the solar radiation is strong.
Problems
Persistent Slabs
A buried crust on south facing slopes continues to be sensitive to human triggering. Short periods of sunshine may increase likelihood of triggering on south facing features.
A spotty layer of surface hoar buried on sheltered and shaded terrain features at treeline has also shown recent reactivity.
The most reactivity has been seen in Valemount and Blue River area. More information can be found here in the new forecaster blog.
Aspects: All aspects.
Elevations: All elevations.
Likelihood
Expected Size
Wind Slabs
Recent snow and moderate southwest winds have formed wind slabs at higher elevations.
These slabs may be surprisingly deep and propagate widely where they are sitting on a weak layer of surface hoar or a sun crust.
Aspects: North, North East, East, South East, South, North West.
Elevations: Alpine, Treeline.
Likelihood
Expected Size
Valid until: Mar 21st, 2022 4:00PM
