Avalanche Forecast
Issued: Apr 20th, 2019 4:32PM
The alpine rating is , the treeline rating is , and the below treeline rating is Known problems include Storm Slabs and Loose Wet.
conrad janzen,
Parks Canada
A very widespread cycle of natural and skier triggered avalanches up to size 3 was observed Saturday. Steep slopes will remain primed for human triggering on Sunday. Make conservative terrain choices until the storm snow has a chance to bond.
Summary
Weather Forecast
Cool temperatures with freezing levels at valley bottom are expected Saturday night. Generally clear skies (lots of solar heating!) and light W winds are expected on Sunday. Monday looks similar with a bit more wind and slightly warmer temperatures.Â
Snowpack Summary
60-100 cm of snow in the last week with snowpack depths reaching seasonal highs above 2000 m. Strong to extreme W winds with 20-40+ cm of snow on Friday created widespread storm slabs in alpine areas and sluffing in steep terrain. This recent snow sits on a variety of surfaces above treeline. Moist snow at lower elevations and on solar aspects.Â
Avalanche Summary
On Saturday Visitor Safety staff observed widespread natural and skier triggered slab avalanches up to size 3 above 2000 m with 1-2 m thick crowns, especially on North and East aspects. Wet loose avalanches were observed to size 2 at lower elevations and steep south aspects, with sluffing on steep N aspects and several new cornice failures.
Confidence
Problems
Storm Slabs
Significant snowfall over the last week combined with two periods of strong to extreme wind has created widespread storm slabs in the alpine. These are primed for human triggering. Minimize exposure to large slopes and cornices in the alpine.
- New snow will require several days to settle and stabilize.
- Use conservative route selection, stick to supported terrain features, avoid overhead hazards.
Aspects: All aspects.
Elevations: Alpine, Treeline.
Likelihood
Expected Size
Loose Wet
Lower elevations and South aspects will have a crust from Saturday, but intense solar inputs will weaken these crusts on Sunday allowing for wet loose avalanches later in the day. Travel and return early before things heat up.
- If triggered, loose wet sluffs may step down to deeper layers resulting in larger avalanches.
- Use extra caution on slopes if the snow is moist or wet.
Aspects: All aspects.
Elevations: All elevations.
Likelihood
Expected Size
Valid until: Apr 21st, 2019 4:00PM
