Avalanche Forecast
Issued: Feb 12th, 2021 4:00PM
The alpine rating is , the treeline rating is , and the below treeline rating is Known problems include Persistent Slabs and Wind Slabs.
ghelgeson,
Avalanche Canada
Human triggered avalanches remain possible, but time and cold temperatures have reduced their sensitivity to triggering. Watch for wind slabs in funny places in the alpine as east/southeast winds continue to blow. Read about managing these conditions in this forecaster blog.
Summary
Confidence
Moderate - Uncertainty is due to extremely variable snowpack conditions reported through the region.
Weather Forecast
Brrrr! Cold temperatures look to be with us through the weekend. The weather models are hinting at more seasonal temperatures beginning Tuesday.
FRIDAY NIGHT: Overnight low temperature around -30 C, moderate southeast wind, no snow expected.
SATURDAY: A few clouds, daytime high temperature around -15 C, strong southeast wind, no snow expected.
SUNDAY: Broken cloud cover, daytime high temperature around -10 C, moderate to strong west/southwest wind, no snow expected, potential for a few cm of snow Sunday night.
MONDAY: Broken cloud cover, daytime high temperature around -5 C, moderate to strong west wind, trace of snow possible.
Avalanche Summary
This avalanche was spotted around Tete Juane, sounds like an older avalanche, likely ran before the cold snap. Other than that there have been no recent avalanche observations.
There were a few small human triggered avalanches reported around treeline near Pine Pass last weekend. These failed on the recently buried surface hoar layer.Â
There were some other observations from throughout the region over the weekend that would suggest ongoing instability associated with that weak surface hoar layer. Reports ranged from whumpfs and shooting cracks, to visual observations of large surface hoar crystals
On February 3rd there were reports of numerous natural avalanches 20 to 40 cm in depth running at and above treeline. A southwest slope produced a size 3 natural avalanche. These avalanches presumably ran on surface hoar which was producing very touchy conditions. There are some great visuals of this activity in this MIN.
Snowpack Summary
There is about 25-50 cm of snow resting on buried surface hoar which is most prevalent above 1600 m. It likely reaches into the alpine too, we're just not sure how high it extends. It may be present down in the trees in some places too. This surface hoar seems to be deepest, and most sensitive to triggering around the McBride area.
Below 1600 m this snow sits on a crust.Â
There are presently no deeper concerns in the snowpack.
Terrain and Travel
- Be careful as you transition into wind affected terrain.
- Avoid open slopes and convex rolls at and below treeline where buried surface hoar may be preserved.
- Carefully evaluate big/extreme terrain features before committing to them, it's not full "go" time yet.
Problems
Persistent Slabs
A surface hoar layer buried near the end of January is now down 25 to 50 cm and was quite sensitive to human triggering last week. Cold temperatures have likely helped to reduce activity on this interface, but it's still there and human triggered avalanches remain possible. This interface seems to be deepest and most sensitive to human triggering in the McBride area. This layer has been most sensitive right at treeline, but it may extend up into the alpine, and/or down into the trees in some locations.
Aspects: All aspects.
Elevations: Treeline, Below Treeline.
Likelihood
Expected Size
Wind Slabs
We're expecting more wind from the east and southeast this weekend which could form fresh wind slabs in unusual locations.
Aspects: All aspects.
Elevations: Alpine.
Likelihood
Expected Size
Valid until: Feb 13th, 2021 4:00PM
