Avalanche Forecast
Issued: Mar 7th, 2024 4:00PM
The alpine rating is , the treeline rating is , and the below treeline rating is Known problems include Persistent Slabs and Wind Slabs.
jpercival,
Avalanche Canada
Buried weak layers persist and are capable of triggering significant and destructive avalanches.
Summary
Confidence
Moderate
Avalanche Summary
Tuesday's reports included a few skier and machine-triggered size 2 (large) persistent slabs in the Coquihalla corridor. An observation flight also confirmed a widespread natural avalanche cycle took place at the end of last week with avalanches reaching size 3 (very large).
Check out this MIN report from the thick of the action on Saturday in the Coquihalla.
Professionals remain concerned about preserved weak layers and very cautious about entering avalanche terrain
Snowpack Summary
Light new snow amounts and a new melt-freeze crust (on solar aspects) have begun to reshape the surface.
Otherwise, 60-100 cm of recent storm continues to settle above a problematic facet/surface hoar/crust layer buried beneath it. This layer has acted as the failure plane in many recent avalanches in this region and adjacent regions and it continues to produce whumpfs and concerning snowpack test results at treeline.
In some areas a second, thicker crust with weak facets above either replaces or is buried just below the layer described above. It similarly continues to produce concerning snowpack test results and may also have been involved in some of the region's recent avalanche activity.
Weather Summary
Thursday night
Mainly cloudy. 10-20 km/h southwest or west alpine winds. Freezing level to valley bottom.
Friday
Cloudy with 1-5 mm of precipitation. 30-40 km/h southwest alpine winds. Treeline temperature 1 °C with freezing level rising to 2000 m.
Saturday
Mainly cloudy with isolated flurries 1-5 cm. 30-50 km/h southwest alpine winds. Treeline temperature reaching 0 °C with freezing levels around 1700 m.
Sunday
Cloudy with flurries bringing 5-10 cm of new snow. 40-50 km/h south alpine winds. Treeline temperature -2 with freezing level falling to 1300 m.
More details can be found in the Mountain Weather Forecast.
Terrain and Travel Advice
- Fresh snow rests on a problematic persistent slab, don't let good riding lure you into complacency.
- Remote triggering is a concern, watch out for adjacent and overhead slopes.
- Watch for newly formed and reactive wind slabs as you transition into wind affected terrain.
Problems
Persistent Slabs
Buried weak layers are most concerning at treeline elevations. Small avalanches may step down to this layer resulting in very large, destructive avalanches.
Aspects: All aspects.
Elevations: All elevations.
Likelihood
Expected Size
Wind Slabs
Recent storm snow may still react as a slab in wind affected features at higher elevations. Watch for deeper and more reactive slabs near ridgelines.
Recent northwest winds mean new slabs may be found on a range of aspects.
Aspects: All aspects.
Elevations: Alpine, Treeline.
Likelihood
Expected Size
Valid until: Mar 8th, 2024 4:00PM
