Avalanche Forecast
Issued: Feb 27th, 2021 4:00PM
The alpine rating is , the treeline rating is , and the below treeline rating is Known problems include Storm Slabs and Persistent Slabs.
kdevine,
Avalanche Canada
Watch for changing conditions as strong winds may mean that storm slabs become increasingly reactive throughout the day. Avoid overhead hazard during times of rapid loading due to strong winds.
There is the potential to trigger deeper weak layers. Choose conservative terrain.
Summary
Confidence
Weather Forecast
SATURDAY NIGHT - Cloudy with flurries, 5-10 cm / moderate to strong southwest wind / alpine low temperature near -12
SUNDAY - Mainly cloudy with scattered flurries, 5 cm / strong west wind / alpine high temperature near -5 / freezing level 1500 m
MONDAY - Mainly cloudy / strong southwest wind / alpine high temperature near -6 / freezing level 1500 m
TUESDAY - Mainly cloudy with flurries / moderate southwest wind / alpine high temperature near -7 / freezing level 1300 m
Avalanche Summary
On Friday, there were several reports of size 1-1.5 human triggered avalanches, as well as one size 2.5 natural avalanche at 2250 m on a southwest to west aspect.
There was also a report of a human-triggered size 2 avalanche that resulted in a full burial in a cutblock near Blue River on Friday. Check out the MIN report here.
On Thursday, there were numerous reports of human-triggered size 1-1.5 storm slab, wind slab, and dry loose avalanches. There were also a few reports of natural avalanches up to size 3 in the neighbouring Glacier National Park region.
On Wednesday there were two explosives-triggered size 3 persistent slab avalanches reported on east to southeast aspects around treeline. These were notable as they failed on the late January persistent weak layer.
There was a widespread natural and explosives-triggered avalanche cycle last weekend and into Monday, with avalanches reported up to size 4. The largest of these avalanches were reported in the Selkirks.
Snowpack Summary
5-10 cm of snow on Saturday night adds a little refresh to the 60-100 cm that has fallen in the past week. Deep wind deposits may be found in lee terrain features in the alpine and open treeline areas, and will likely remain reactive to human triggers. All of this new snow sits over weak, faceted snow from the recent cold snap.
There is now 70-120 cm of snow above the late January persistent weak layer which is composed of surface hoar in sheltered areas in the trees and/ or a crust on steep solar aspects.
Terrain and Travel
- Watch for newly formed and reactive wind slabs as you transition into wind affected terrain.
- Be aware of highly variable recent wind loading patterns.
- Storm slabs in motion may step down to deeper layers resulting in large avalanches.
- Use conservative route selection and resist venturing out into complex terrain.
Problems
Storm Slabs
Storm slabs may continue to be reactive, especially in wind-loaded areas at higher elevations. Variable winds in recent days may mean that wind loading can be found on all aspects.
Aspects: All aspects.
Elevations: All elevations.
Likelihood
Expected Size
Persistent Slabs
There are several persistent weak layers in the snowpack. The most recent is down 40-80 cm and was formed during the recent cold snap.
The late January persistent weak layer is down 70-120 cm. Though avalanches on this layer have been sporadic, they have been large.
Aspects: All aspects.
Elevations: All elevations.
Likelihood
Expected Size
Valid until: Feb 28th, 2021 4:00PM
