Avalanche Forecast

Issued: Apr 14th, 2023 2:00PM

The alpine rating is considerable, the treeline rating is moderate, and the below treeline rating is below threshold. Known problems include Wind Slabs, Persistent Slabs and Deep Persistent Slabs.

Avalanche Canada mkoppang, Avalanche Canada

A warm day is forecast for Saturday with clear skies in the AM then convective flurries in the PM. Watch for solar radiation to decrease stability on solar aspects as the day warms up. Pay attention to overhead terrain that may be in the sun at the start of your day. Early startsand finishes are key! Its heading to spring!!!

Summary

Confidence

Moderate

Avalanche Summary

A few loose wet avalanches were observed on Friday but no new slab activity was noted.

Snowpack Summary

Cooler temperatures have helped stabilize the snowpack where previously it lacked structure and was rain soaked. This is mainly below 2200m or just below treeline. Above this elevation the snow was drier and windslabs formed with the strong SW flow. These windslabs are overlying a variety of different surfaces from crusts on solar aspects to dry snow on more polar. Carefully evaluate this bond as you travel. A deeper persistent layer down 1m was active in many avalanches over the past few days. This layer was most active on N and E aspects. Treat any area that have not slid as suspect and requires careful evaluation or imply avoidance. Deeper in the snowpack the weak facets and depth hoar at the base of the snowpack is still there. As temps warm up and this layer begins to settle and squish out it will improve and begin to bond but for now, its still a layer to think about as you travel. Thin areas is where you may be able to trigger this weakness. Solar radiation has a big influence on stability at this time of year. Stability will quickly deteriorate on solar aspects as temperatures warm up. These decreases will be most apparent on steep solar aspects, especially in thin rocky terrain. Early starts and finishes that avoid the heat of the day are key. Also pay close attention to what aspect you are on or under.

Weather Summary

Saturday will start with mostly clear skies, but by mid morning clouds will build. An overnight low of about -15 is expected with a rise in temperatures later in the morning. The high will be -3ish, but with the sun factored in low elevation areas will be above zero by noon. Convective flurries will appear in the afternoon, giving a modest 2cm. Winds will be light from the SW. Freezing level 2000m. What important to note is the solar radiation. It is intense at this time of year so expect stability to decrease on sola aspects early in the day.

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.
  • Watch for newly formed and reactive wind slabs as you transition into wind affected terrain.

Problems

Wind Slabs

An icon showing Wind Slabs

Windslabs in the recent storm snow should be expected at treeline and above. Evaluate the bond with the underlying snowpack which is highly variable. There is lots of uncertainty at this interface currently.

Aspects: All aspects.

Elevations: Alpine.

Likelihood

Possible - Likely

Expected Size

1 - 2

Persistent Slabs

An icon showing Persistent Slabs

The persistent layer down 1m has been active due to recent snow loads. It also appears to be sensitive to heat.

Aspects: North, North East, East, South East.

Elevations: Alpine, Treeline.

Likelihood

Likely

Expected Size

1.5 - 2.5

Deep Persistent Slabs

An icon showing Deep Persistent Slabs

This layer has calmed down a bit, but if it warms up quickly expect it to come back to life.

Aspects: All aspects.

Elevations: Alpine, Treeline.

Likelihood

Likely

Expected Size

2 - 3.5

Valid until: Apr 15th, 2023 4:00PM