Avalanche Forecast
Issued: Apr 21st, 2021 4:00PM
The alpine rating is , the treeline rating is , and the below treeline rating is Known problems include Cornices.
shorton,
Avalanche Canada
Cool cloudy weather has made for generally safe avalanche conditions. Be careful around cornices and the isolated areas where the snowpack isn't capped by a thick crust.
Summary
Confidence
High - The snowpack structure is mostly striaghtforward and not unusually variable.
Weather Forecast
A shift to cooler cloudy weather as a cold front crosses the region on Wednesday night.
WEDNESDAY NIGHT: Cloudy with a thin dusting of new snow, 40 km/h northeast wind, freezing level drops to valley bottom with treeline temperatures dropping to -10 C.
THURSDAY: Clouds clearing in the morning then sunny in the afternoon, light north wind, freezing level climbs to 1200 m with treeline temperatures around -4 C.
FRIDAY: Mostly cloudy skies, light southwest wind, freezing level climbs to 1200 m with treeline temperatures around -4 C.
SATURDAY: Mostly cloudy skies, light northeast wind, freezing level climbs to 1500 m with treeline temperatures around -2 C.
Avalanche Summary
Warm sunny weather on Monday and Tuesday likely resulted in wet loose avalanche activity on steep sun-exposed slopes. We have several reports of avalanche activity triggered by last week's warming including widespread wet loose avalanches and a few large (size 3) wet slab avalanches in the McBride area.
The cooling trend will make wet avalanches problems less likely in the coming days, making isolated wind slabs and cornice falls the primary concern.
Snowpack Summary
A dusting of new snow will sit above a thick surface crust. Up to 5 cm of snow is expected along the Robson Valley with little to no snow further south and west. The upper snowpack has been undergoing a daily melt-freeze cycle, so with the cooling temperatures a hard crust will form everywhere except in high north-facing terrain where there still may be dry snow above roughly 2300 m.Â
We suspect older weak layers have gone inactive as the weather patterns over the past month have been favourable for strengthening the snowpack. That being said, we have very limited field observations to confirm this so make sure to back off if you notice signs of instability.
Terrain and Travel
- When a thick, melt-freeze surface crust is present, avalanche activity is unlikely.
- Pay attention to cornices and give them a wide berth when traveling on or below ridges.
- Carefully evaluate steep lines for wind slabs.
- Minimize exposure to steep, sun exposed slopes, especially when the solar radiation is strong.
Problems
Cornices
Minimize your exposure below cornices. Cornice falls are dangerous on their own and can possibly trigger avalanches on slopes below.
Aspects: North, North East, East, South East, North West.
Elevations: Alpine.
Likelihood
Expected Size
Valid until: Apr 22nd, 2021 4:00PM
