Avalanche Forecast

Issued: Apr 14th, 2017 3:00PM

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

Alberta Parks mike.koppang, Alberta Parks

Strong winds are creating new windslabs in Alpine areas.  Pay close attention to the input of solar radiation as you travel in relation to overhead terrain.  Freezing levels are forecast to be valley bottom overnight.

Summary

Confidence

Moderate - Timing or intensity of solar radiation is uncertain on Saturday

Weather Forecast

No new snow is forecast over the next 24hrs and temperatures are still forecast to remain cool.  Winds will continue to be strong out of the SW which will help to keep the snowpack cooler but when the sun comes out, stability will quickly deteriorate on solar aspects, especially steeper or rocky terrain. 

Avalanche Summary

A few loose wet slides were observed that had likely come out after the forecasting day on Thursday.  Otherwise, there were no new avalanches on friday. 

Snowpack Summary

Only a skiff of new snow over the past 24hrs.  Of note the winds were howling (aka strong) out of the SW at higher elevations.  Widespread snow transport was observed in alpine terrain and as a result new windslabs were forming at higher elevations on lee aspects.  Temperatures remained somewhat cool but we did see some moist snow later in the afternoon on solar aspects.  On Thursday the warm temps had moist snow up to 2400m on all aspects.  As a result, surface crusts should be expected in most areas making the skiing challenging. Dry powder snow is pretty much only likely in high alpine areas on North aspects.  On solar aspects, crusts are bing observed up to 2700m.

Problems

Wind Slabs

An icon showing Wind Slabs
Fresh windslabs are forming on lee aspects (N and E) in alpine areas as a result of strong SW winds on friday.
Avoid freshly wind loaded features.

Aspects: North, North East, East.

Elevations: Alpine.

Likelihood

Possible - Likely

Expected Size

1 - 2

Deep Persistent Slabs

An icon showing Deep Persistent Slabs
We are not entirely free from this layer yet. It is still down there and more suspect in thin areas, cold areas that haven't seen a warming cycle and large terrain that hasn't avalanched yet.
Be aware of thin areas that may propogate to deeper instabilites.Avoid exposure to overhead avalanche terrain, large avalanches may reach the end of run out zones.Pay attention to overhead hazards like cornices which could easily trigger deep slabs.

Aspects: All aspects.

Elevations: Alpine, Treeline.

Likelihood

Unlikely - Possible

Expected Size

2 - 3

Valid until: Apr 15th, 2017 2:00PM