Avalanche Forecast
Issued: Apr 5th, 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
The sun will be the biggest factor in tomorrow's avalanche hazard. As the temperatures rise, expect the snowpack to loosen up and become more sensitive to triggering. Loose wet avalanches and cornice falls could be in the cards if the sun exposure is strong enough.
Summary
Confidence
Avalanche Summary
Nothing new was reported or observed today.
Snowpack Summary
Despite the relatively cool temperatures, the snowpack is settling slowly. Recent snowfalls remain dry and largely not effected by wind on polar aspects. On the solar side, surface conditions are turning moist and then re-freezing overnight. However, the snowpack has not yet transitioned to a true "spring" snowpack. Several persistent weak layers remain in the upper and mid snowpack down anywhere from 20 to 80cm. It's worth taking the time to dig down and explore these interfaces as they are highly variable depending on aspect and elevation. Slab avalanches on these interfaces are still possible. And of course, our friendly neighbourhood facet / depth hoar basal layers are still here. These are of more concern in steep, shallow and/or rocky terrain where full-depth avalanches are possible. The strength of the April sun is a factor in "waking up" this deep instability.
Weather Summary
It's looking like tomorrow will be clear to start with some light cloud building during the day. Basically the same convective weather we've seen for awhile now. Morning low of -13, high of -1. Gusty winds, but still light overall. Freezing level of 2100-2200m.
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
Thin, shallow areas or heavy triggers (such as cornices) are what will set this layer off. Avoid terrain with those characteristics. Intense solar radiation and daytime heating may wake up this layer.
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 6th, 2023 4:00PM
