Avalanche Forecast
Issued: Mar 22nd, 2021 4:00PM
The alpine rating is , the treeline rating is , and the below treeline rating is Known problems include Storm Slabs and Cornices.
shorton,
Avalanche Canada
Carefully evaluate steep slopes where recent snow could still produce avalanches, especially in wind affected terrain.
Summary
Confidence
Weather Forecast
MONDAY NIGHT: Clear skies, light northwest wind, freezing level around 1000 m with treeline temperatures drop to -5 C.
TUESDAY: Mix of sun and cloud, 20-30 km/h west wind, treeline temperatures around -3 C.
WEDNESDAY: Cloudy with scattered flurries bringing roughly 20 cm of snow throughout the day, 30-50 km/h southwest wind, freezing level climbs to 1000 m with treeline temperatures around -1 C.
THURSDAY: Mostly sunny, light northeast wind, freezing level climbing to 1300 m with treeline temperatures near 0 C.
Avalanche Summary
Widespread storm slab avalanche activity was reported on Sunday, and preliminary reports from Monday suggest they were still reactive to human triggering. On Sunday numerous size 1-2 natural slab avalanches were observed in the North Shore mountains. These avalanches were mostly 20-30 cm thick and ran on a crust layer. On Monday there were some reports of size 1.5-2 human triggered avalanches in the Seymour backcountry (30-60 cm thick). See the photos here and here. These slabs should be less reactive by Tuesday, but may still be possible to trigger in steep terrain.
Snowpack Summary
35-45 cm of snow from Sunday is settling and strengthening, but could still be unstable on some steep and wind affected slopes. Reports suggest the new snow was poorly bonded to a crust on Sunday, but this should improve quickly. Along ridgelines, cornices are large and always have the potential of failing or being triggered from the weight of a human.
Terrain and Travel
- Exercise caution on steep, unsupported slopes.
- Be careful as you transition into wind affected terrain.
- Use caution above cliffs and terrain traps where even small avalanches may have severe consequences.
- Pay attention to cornices and give them a wide berth when traveling on or below ridges.
Problems
Storm Slabs
Recent snow is strengthening, but the reactivity of storm slabs should still be assessed before approaching steep open terrain. North and east facing slopes are most suspect due to gusty winds from the south and west.
Aspects: All aspects.
Elevations: Alpine, Treeline.
Likelihood
Expected Size
Cornices
Cornices are large and looming along many ridgelines, and have likely grown with the recent snow and wind.
Aspects: North, North East, East, West, North West.
Elevations: Alpine.
Likelihood
Expected Size
Valid until: Mar 23rd, 2021 4:00PM
