Avalanche Forecast
Issued: Apr 30th, 2017 4:29PM
The alpine rating is Loose Wet, Wind Slabs and Deep Persistent Slabs.
, the treeline rating is , and the below treeline rating is Known problems includePay attention to freezing levels this week. The first really big warmup is forecasted for Wednesday when freezing levels are expected to rise to 3000m.
Summary
Weather Forecast
Mixed sun and cloud with some convective flurries are forecast for Monday. Freezing levels will be around 2000 m on Monday and rising significantly to 3000m by Wednesday as an upper ridge moves into the region from the west.
Snowpack Summary
15 cm of overnight snow and 40-60cm of storm snow from this past week. There is moist surface snow and variety of melt freeze crusts in the upper snow pack in all areas except for due north above 2300 m. A basal weakness remains at the bottom of the snow pack. It is currently only reactive to large triggers but may wake up with solar warming.
Avalanche Summary
Several fresh wind slab avalanches (up to size 2) were observed in the alpine on north aspects in the Field and Lake Louise area on Sunday. Loose wet avalanches and several slab avalanches (associated with day time heating) were also observed on Sunday.
Confidence
Problems
Loose Wet
Loose wet avalanches can be expected on solar aspects in the afternoon when the day warms up.
- If triggered the loose wet sluffs may step down to deeper layers resulting in large avalanches.
- Pay attention to sluffing off cliffs and steep solar terrain, signs of a warming snowpack.
Aspects: North, North East, East, South East.
Elevations: All elevations.
Likelihood
Expected Size
Wind Slabs
Recent winds have created soft wind slabs on north aspects in the alpine.
- Be careful with wind loaded pockets, especially near ridge crests and roll-overs.
Aspects: North, North East, East.
Elevations: Alpine.
Likelihood
Expected Size
Deep Persistent Slabs
The weak basal facets can produce large avalanches with large triggers or heat. Remember that the snowpack is generally strongest in the morning when it is cool.
- Pay attention to overhead hazards like cornices which could easily trigger the deep persistent slab.
Aspects: All aspects.
Elevations: Alpine, Treeline.
Likelihood
Expected Size
Valid until: May 1st, 2017 4:00PM