Avalanche Forecast
Issued: Mar 3rd, 2022 4:00PM
The alpine rating is , the treeline rating is , and the below treeline rating is Known problems include Storm Slabs and Persistent Slabs.
shorton,
Avalanche Canada
Evaluate snow and terrain carefully, human triggered avalanches are still possible as recent snow has been slow to strengthen.
Summary
Confidence
Weather Forecast
THURSDAY NIGHT: Partly cloudy skies with scattered flurries bringing up to 5 cm of snow, light wind from the northwest, treeline temperatures drop to -6 C.
FRIDAY: Mix of sun and cloud, no significant precipitation, light wind from the north, treeline temperatures reach -3 C with freezing level climbing to 1500 m.
SATURDAY: Mix of sun and cloud, light wind from the northwest, treeline temperatures around -4 C.
SUNDAY: Mostly sunny skies, light wind from the north, treeline temperatures around -4 C.
Avalanche Summary
Preliminary reports from Thursday suggest storm slabs are still reactive to human triggering, with a report of a size 1.5 avalanche in the alpine in the Selkirks. A large storm slab avalanche cycle occurred on Monday and Tuesday, and on Wednesday there were numerous reports of human triggered avalanches in the top 20 to 50 cm of storm snow. Storm slab avalanches have been running on recently buried crust and surface hoar layers, and in general have been bigger in the Selkirks.
Over the past two weeks we have seen sporadic large (size 2 to 3) persistent slab avalanches on buried surface hoar and crust layers. Most of the activity has been in the Valhalla, Goat, and Kokanee Ranges. Recent weather trends have likely helped stabilize these layers, but we aren't quite ready to rule out the possibility of large persistent slab avalanches in parts of the region. Most recently, we received one report of a size 2 human-triggered persistent slab avalanche at 2200 m in the Valhallas on Wednesday.
Snowpack Summary
Recent storm snow has likely settled into 20 to 40 cm of heavy powder at upper elevations and moist/crusty snow below 2000 m. Reactive slabs may still be found on wind loaded slopes and perhaps some isolated areas where this snow sits above sun crusts or feathery surface hoar. The recent storm delivered more snow to the Selkirks than the Monashees.
The snowpack is generally well settled below the new snow, although there are two potential weak layers buried 50 to 100 cm deep. They both consist of surface hoar and/or melt-freeze crusts. Recent trends suggest these layers have been more reactive in southern Selkirks around the Valhalla, Kokanee, and Goat Ranges. We are uncertain about the reactivity of these layers in the wake of the recent storm and temperature fluctuations.
Terrain and Travel
- If you are increasing your exposure to avalanche terrain, do it gradually as you gather information.
- Investigate the bond of the recent snow before committing to your line.
- Be carefull around freshly wind loaded features.
- Avoid exposure to steep sun exposed slopes.
- Carefully assess open slopes and convex rolls where buried surface hoar may be preserved.
Problems
Storm Slabs
20 to 40 cm of recent storm snow is bonding relatively quickly in most areas, but may still produce avalanches in specific terrain features. This includes steep sun-exposed slopes, wind loaded slopes, and open convexities at treeline where there could be buried sun crusts or surface hoar layers.
Aspects: All aspects.
Elevations: Alpine, Treeline.
Likelihood
Expected Size
Persistent Slabs
Persistent weak layers have gained strength over the past week, but it may still be possible to trigger large avalanches on buried surface hoar or crust layers found 50 to 100 cm deep. The problem is most likely found in the southern part of the Selkirks (e.g. Valhalla, Goat and Kokanee ranges), especially on open convex slopes.
Aspects: All aspects.
Elevations: All elevations.
Likelihood
Expected Size
Valid until: Mar 4th, 2022 4:00PM
