Avalanche Forecast

Issued: Apr 21st, 2017 3:00PM

The alpine rating is below threshold, the treeline rating is below threshold, and the below treeline rating is below threshold. Known problems include Loose Wet, Deep Persistent Slabs and Cornices.

matt.mueller, Alberta Parks

Kananaskis.

Spring is officially here! Our daily forecast will stop as of today, but we will update if needed. Remember that snow stability is directly related to temperatures. Early starts and solid freezes are essential for safe travel.

Summary

Confidence

Weather Forecast

The predictable spring pattern appears to be with us now. The next few days will see daytime freezing levels approach treeline and evening lows just below zero. The winds will be light for the next 3 days. Flurries will also be ongoing, however amounts will be low.

Avalanche Summary

Nothing noted, but our field day was done by 9 am. Likely some loose wet to sz1.5 in the afternoon with the warmth and light rain.

Snowpack Summary

Wet. Last night saw rain up to 2300m with extended warm temps. Eventually the rain turned to snow, but not until late in the night (or early in the morning-depends on how you look at it). This made for a very marginal freeze with 5-10cm of moist snow on the surface. Right now valley bottom snow is isothermal, treeline snow is seeing a daily freeze/thaw cycle and the alpine is seeing surface crusts on all aspects that are gradually penetrating to the deeper layers. A late, but classic spring change to the entire snowpack is underway. With the extended warmth cornices are an increasing problem. Treat them with caution, whether they are above or next to you.

Problems

Loose Wet

As the snowpack warms we become increasingly susceptible to loose wet avalanches. Steep terrain and gullies should be treated with caution if the snow is moist or wet.

Use extra caution on slopes if the snow is moist or wet.If triggered the loose wet sluffs may step down to deeper layers resulting in large avalanches.

Aspects: All aspects.

Elevations: All elevations.

Likelihood

Likely

Expected Size

1 - 3

Deep Persistent Slabs

In general the bottom layers are still weak and suspect. Especially in the alpine and/or polar aspects. Wet slabs are also a possibility as the deeper layers fail.

Avoid exposure to overhead avalanche terrain, large avalanches may reach the end of run out zones.

Aspects: All aspects.

Elevations: All elevations.

Likelihood

Possible

Expected Size

2 - 3

Cornices

Cornices are collapsing with the warmer temperatures triggering slabs on underlying slopes.

Extra caution needed around cornices with current conditions.Stay well back from cornices.

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

Elevations: Alpine.

Likelihood

Likely - Very Likely

Expected Size

2 - 3

Valid until: Apr 22nd, 2017 2:00PM