Avalanche Forecast
Issued: Apr 21st, 2023 4:00PM
The alpine rating is , the treeline rating is , and the below treeline rating is Known problems include Wind Slabs and Deep Persistent Slabs.
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Avalanche Canada
It's a challenge to manage different avalanche concerns that vary by elevation and aspect. Observe local conditions and use that information to help select terrain and travel techniques.
Expect spring conditions at elevations up to around treeline,and solar aspects well into the alpine. Warm temperatures melt the strength out of the snow so avoid avalanche terrain in these areas when it's sunny, late in the day, or if there isn't an overnight freeze.
Summary
Confidence
Moderate
Avalanche Summary
No new avalanches reported. Previous reports (or new reports of previous avlanche activity) speak to solar triggered avalanches up to size 2.5 in the afternoon. Please remember there are few eyes still out there regularly reporting field observations.
Snowpack Summary
Continued light snow fall amounts at higher elevations and north-facing slopes towards treeline. All this recent snow is settling and bonding about as fast as more arrives. Windslabs are possible in immediate lee features.
On solar aspects at all elevations, and north aspects treeline and below, the recent snow either overlies a widespread melt-freeze crust or there is a crust at the surface. Watch for surface snow becoming moist in the afternoon.
The middle of the snowpack is generally well-settled and strong. A weak layer of facets at the base of the snowpack remains a concern, primarily in alpine terrain with shallow or variable (thick and thin) snowpack depths but also where there's overhead hazard (for example from cornices).
Weather Summary
Friday Overnight
Cloudy with clear periods. Flurries in places but only trace to 2 cm of precipitation. Light southwest ridgetop winds. Treeline temperatures around -5 C. Freezing level falling to valley bottom.
Saturday
Cloudy with flurries. Just a trace to 5 cm of snow. Moderate southwest ridgetop winds. Treeline temperatures around zero to -5 C. Freezing level around 1900 m.
Sunday
Warm overnight temperatures with freezing level remaining around 1500m. Cloudy with snow, accumulations up to 10 cm by end of day. Moderate southerly winds. Treeline temperatures around -3 and freezing level around 2000 to 2200 m.
Monday
Warm overnight temperatures with freezing level remaining around 1500m. Cloudy with another 5 to 10 cm of snow. Moderate southwest winds. Treeline temperatures around -3 and freezing level around 2000 m.
More details can be found in the Mountain Weather Forecast.
Terrain and Travel Advice
- If you are increasing your exposure to avalanche terrain, do it gradually as you gather information.
- Be alert to conditions that change with elevation and sun exposure.
- Investigate the bond of the recent snow before committing to your line.
- Be carefull around freshly wind loaded features.
- In areas where deep persistent slabs may exist, avoid shallow or variable depth snowpacks and unsupported terrain features.
Problems
Wind Slabs
With recent wind, and various amounts of new snow, anticipate fresh wind slab development. Watch for these wind slab pockets, primarily at higher elevations where cold, dry snow persists. Dial back your terrain choices if you encounter more than 20 to 30 cm of new snow.
Aspects: All aspects.
Elevations: Alpine.
Likelihood
Expected Size
Deep Persistent Slabs
A weak layer of facets exists near the base of the snowpack. Thinner snowpack areas and areas with variable thick and thin coverage at alpine elevations is where this problem is most likely found. April's warming temperatures may gradually increase the sensitivity of this layer, especially in thin snowpack areas.
Aspects: All aspects.
Elevations: Alpine.
Likelihood
Expected Size
Valid until: Apr 22nd, 2023 4:00PM
