Avalanche Forecast

Issued: Feb 17th, 2023 3:15PM

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

Avalanche Canada mkoppang, Avalanche Canada

A few cms of snow over the past few days is adding up to around 10cm at treeline. This snow is adding load to the windslabs that formed earlier in the week. The snowpack still has an overall weak structure and a weak base and big features should be avoided.

Summary

Confidence

High

Avalanche Summary

One new sz 2.5 Slab was observed south of Black prince on Friday that ran full path but did not fail to ground. A few other small slabs were also observed and a few loose dry slides up to sz 1.

Snowpack Summary

10cm of snow fell at treeline on Friday with light winds from the west. This new snow is overlying a temperature crust on solar aspects up to 2400m throughout the range. Treeline and alpine windslabs continue to be the main avalanche concern in terms of "triggerability". They are improving with the the relatively warm temperatures, but still expect to find reactive pockets in steep and/or convex terrain. In terms of consequence, the dreaded Nov 5 facets still have a firm grip on the low probability/high consequence title. Some of our neighbours to the west have seen failures on this layer, which suggest that new snow loading or a wind slab trigger is a critical factor for when this layer will fail.

Weather Summary

Overnight on Friday the light flurries will continue and day time temperatures on Saturday will be around -8C. Winds will initially be strong out of the west and decrease throughout the day.

More details can be found in the Mountain Weather Forecast.

Terrain and Travel Advice

  • Avoid shallow, rocky areas where the snowpack transitions from thick to thin.
  • Watch for newly formed and reactive wind slabs as you transition into wind affected terrain.
  • Be aware of the potential for surprisingly large avalanches due to deeply buried weak layers.

Problems

Wind Slabs

An icon showing Wind Slabs

Open slopes at treeline and alpine areas look plump and ready for a trigger. Low angle terrain is still key.

Aspects: All aspects.

Elevations: Alpine, Treeline.

Likelihood

Possible

Expected Size

1 - 2

Deep Persistent Slabs

An icon showing Deep Persistent Slabs

Thin areas are where this layer will be easiest to trigger. Be thinking about wide propagations as the snowpack above is more cohesive than before.

Aspects: All aspects.

Elevations: Alpine, Treeline.

Likelihood

Possible

Expected Size

2 - 3

Valid until: Feb 18th, 2023 4:00PM