Avalanche Forecast
Issued: Apr 8th, 2023 4:00PM
The alpine rating is , the treeline rating is , and the below treeline rating is Known problems include Deep Persistent Slabs and Persistent Slabs.
matt,
Avalanche Canada
We are starting to see spring win the snowpack war. The cost of this victory will be a period (now) of an unpredictable snowpack with large avalanches becoming the norm. Give the big, steep lines the space and respect they deserve. Instead, enjoy the mellow slopes or the walking alpine tours.
Summary
Confidence
Avalanche Summary
Nothing was reported today (as of 3pm). We didn't get a field trip in today, so don't put a lot of weight on the lack of observations.
Snowpack Summary
Once again the warmth is lingering overnight. Valley bottoms are almost above zero 24hrs a day and freezing levels are creeping higher and higher. With the warmth penetrating deeper and deeper into the snowpack we are anticipating a continued weakening of the snowpack. There will be light surface recovery, but the mid pack will retain some of the heat from the day. This is the start of the freeze thaw cycle we've all been waiting for. Unfortunately this means a touchy snowpack for the next while. The pesky Nov deep persistent problem appears to be waking up and as expected, its causing lots of trouble. It will become more reactive as the mid-pack warms up.
Weather Summary
Tomorrow will see the warm weather continue (as it should! enough his enough). Temperatures on Saturday were above freezing for most of the day, and a marginal re-freeze is expected tonight. Saturday's high will be just above zero, but when the solar is factored in it will be much warmer. We may get a few flurries along the way, but not much only a few flakes here and there. Winds will continue to be from the SW and generally light/moderate(20-30km), but gusting into the strong(50km) range.
More details can be found in the Mountain Weather Forecast.
Terrain and Travel Advice
- In areas where deep persistent slabs may exist, avoid shallow or variable depth snowpacks and unsupported terrain features.
- Minimize exposure to sun-exposed slopes when the solar radiation is strong.
Problems
Deep Persistent Slabs
Up to now this layer has been somewhat shielded by a mediocre mid-pack. As this mid-pack warms up it will not have a bridging effect anymore. This layer will become more touchy as heat gets absorbed into the snowpack. This weakening applies to ALL terrain. Even polar terrain or slopes with recent tracks on them. Tread cautiously and avoid overhead exposure.
Aspects: All aspects.
Elevations: Alpine, Treeline.
Likelihood
Expected Size
Persistent Slabs
There are two layers of concern here: 1) a buried sun crust (on solar) and facets (on polar) down 20-40cm, and 2) a facet/depth hoar layer down 80-100cm that was buried mid season. The sensitivity of these layers is highly variable so take the time to dig down and evaluate the snowpack. These avalanche problems are more prone to triggering during periods of intense solar radiation.
Aspects: All aspects.
Elevations: Alpine, Treeline.
Likelihood
Expected Size
Valid until: Apr 9th, 2023 4:00PM
