Avalanche Forecast
Issued: Feb 18th, 2023 4:00PM
The alpine rating is , the treeline rating is , and the below treeline rating is Known problems include Wind Slabs and Deep Persistent Slabs.
rbuhler,
Avalanche Canada
Wind slabs are expected to remain reactive to human triggering on Sunday.
It is also important to remember that a weakness exists at the base of the snowpack in parts of the region and very large deep persistent slab avalanches remain possible.
Summary
Confidence
Avalanche Summary
An early report from Saturday includes several natural and skier-triggered size 1 loose dry avalanches as well as a few small pockets of wind slab. Earlier in the week, a couple of bigger wind slabs were reported including this MIN post and this MIN post.
The deep persistent slab problem continues to be a concern for parts of the region. In the nearby Bull River area, this very large older avalanche was observed on Friday by the Avalanche Canada field team which is expected to have occurred on Wednesday.
Snowpack Summary
For the most part, the upper snowpack has been heavily altered by the wind and, on south aspects, the sun. That being said, opportunities to avoid lingering wind slabs and find softer snow still exist in sheltered, mostly north facing terrain features.
The middle of the snowpack is well consolidated and sits on a thick crust. The bottom of the snowpack still consists of weak, sugary crystals that are slowly gaining strength in areas with a deeper snowpack.
Deep persistent slab avalanches should still be on your radar in thinner snowpack areas outside of the Lizard Range such as the Bull River, Elkford, and the Flathead.
Weather Summary
Saturday night
Partly cloudy, possibly clearing by morning, light to moderate W-NW wind, treeline low around -10 ˚C.
Sunday
A mix of sun and cloud in the morning, cloudy in the afternoon with light flurries, moderate to strong SW-W wind, treeline high around -5 ˚C.
Monday
Snowfall beginning overnight 15-30 cm, moderate to strong SW-W wind, easing in the afternoon, treeline high around -6 ˚C.
Tuesday
Snowfall 15-30 cm overnight with another 5-15 cm during the day, moderate to strong SW wind switching to NE by the end of the day, treeline temperature dropping to around -20 ˚C.
More details can be found in the Mountain Weather Forecast.
Terrain and Travel Advice
- Watch for areas of hard wind slab on alpine features.
- Seek out wind sheltered terrain below treeline where you can avoid wind slabs and find great riding.
- Pay attention to cornices and give them a wide berth when traveling on or below ridges.
- Avoid thin areas like rock outcroppings where you're most likely to trigger avalanches failing on deep weak layers.
Problems
Wind Slabs
Older large wind slabs may still linger in immediate leeward and cross-loaded features. Also watch for signs of new wind slab formation, especially if we receive more than just light snow flurries on Sunday afternoon.
Aspects: North, North East, East, South East, South, North West.
Elevations: Alpine, Treeline.
Likelihood
Expected Size
Deep Persistent Slabs
A layer of faceted grains near the base of the snowpack remains on the radar for areas of this region where the snowpack is shallow and not capped by a hard melt-freeze crust that formed in late December. This describes most areas outside of the Lizard Range such as the Bull River, Flathead, and Elkford.
Aspects: All aspects.
Elevations: Alpine, Treeline.
Likelihood
Expected Size
Valid until: Feb 19th, 2023 4:00PM
