Avalanche Forecast
Issued: Apr 18th, 2021 4:00PM
The alpine rating is , the treeline rating is , and the below treeline rating is Known problems include Wind Slabs.
astclair,
Avalanche Canada
Watch for wind slabs in drifted areas at upper elevations, especially near ridge-crests, roll-overs, and in steep terrain.
Summary
Confidence
Moderate - Forecast snowfall amounts are uncertain.
Weather Forecast
Sunday night: Cloudy, up to 5 cm of snow, moderate northeast winds, alpine temperature -10 C, freezing level dropping to valley bottom.
Monday: Mostly cloudy, light northerly winds, alpine high temperature -3 C, freezing level 1700 m.
Tuesday: Sunny, light southerly winds, alpine high temperature -2 C, freezing level 2300 m.Â
Wednesday: Sunny, light southwest winds, alpine high temperature -3 C, freezing level 2500 m.Â
Avalanche Summary
On Saturday, there were reports of numerous wet loose avalanches releasing naturally on steep east-facing alpine slopes early in the day. Observers also reported two natural wet slab avalanches that occurred on northeast aspects above 2000 m.
Snowpack Summary
An upslope storm brought 5-10 cm of new snow to the region, with 20+ cm accumulating in favored areas. Moderate northeast winds with strong ridgetop gusts have formed fresh wind slabs in exposed areas at upper elevations. Cornices are large and fragile. Cornice falls could trigger avalanches on the slopes below.Â
The snowpack is overall strong and settled in most areas. However, steep and rocky alpine slopes with a shallow or thin to thick snowpack may still harbor deeply buried weak layers.
The snow line is slowly creeping up the mountains, making some access areas snow-free.Â
Terrain and Travel
- Watch for newly formed and reactive wind slabs as you transition into wind affected terrain.
- Stay off recently wind loaded slopes until they have had a chance to stabilize.
- Avoid freshly wind loaded features, especially near ridge crests, roll-overs and in steep terrain.
- Extra caution is needed around cornices under the current conditions.
Problems
Wind Slabs
New snow totals varied across the region, with anywhere from 5-20 cm of accumulation. The new snow combined with moderate northeast winds has likely formed fresh wind slabs in lee terrain features that may be reactive to human triggers.
Aspects: North, East, South East, South, South West, West, North West.
Elevations: Alpine, Treeline.
Likelihood
Expected Size
Valid until: Apr 19th, 2021 4:00PM
