Avalanche Forecast

Issued: Nov 28th, 2017 3:39PM

The alpine rating is considerable, the treeline rating is considerable, and the below treeline rating is moderate. Known problems include Storm Slabs.

Avalanche Canada mgrist, Avalanche Canada

The new snow will take time to settle and bond to a prominent crust. Dial back your terrain choices until conditions stabilize. Due to limited data it is CRITICAL to supplement this information with your own observations.

Summary

Confidence

Moderate - Timing, track, or intensity of incoming weather system is uncertain

Weather Forecast

We're looking at a brief lull in the active weather pattern on Wednesday, before the next system arrives on Thursday with modest amounts of snow.WEDNESDAY: Clearing throughout the day. Moderate westerly ridgetop winds. Freezing level around 1200 m.THURSDAY: Snow (10-15 cm). Moderate southwesterly ridgetop winds. Freezing level around 1000 m. FRIDAY: Cloudy with sunny breaks during the day and isolated flurries. Moderate south west ridgetop winds. Freezing level around 1000 m.

Avalanche Summary

On Monday we had reports of a natural Size 2 avalanche near Kootenay Pass. See here for the MIN report, along with some good snowpack information. We currently have very limited observations in this region. Please submit your observations to the Mountain Information Network (MIN).

Snowpack Summary

Anywhere from 2-10 cm of snow fell Sunday overnight into Monday, as temperatures dropped by 5-10 degrees (and back to more seasonal values). Ridge top winds were moderate from the west and likely formed wind slabs on lee (easterly) slopes.This new snow fell on a 2 cm thick melt-feeze crust (the November 27th crust), which could become a good sliding layer during Tuesday's storm.The depth of the snowpack varies greatly with elevation. Recent reports suggest the average depth is 100-170cm in the alpine, 50-100cm at treeline, and decreasing rapidly below treeline where the primary hazards are rocks, stumps, and open creeks. Last week's heavy rain to the mountaintops really shrunk the snowpack and has transitioned much of the snowpack from dry to moist snow. We currently have very limited snowpack observations within this region and it is critical to supplement this information with your own observations.

Problems

Storm Slabs

An icon showing Storm Slabs
New snow on Tuesday into Wednesday will sit on a 2 cm thick melt-freeze crust, which will likely act as a good sliding layer.
Use caution in lee areas. Recent wind loading has created wind slabs.Minimize overhead exposure during periods of heavy loading from new snow, wind.

Aspects: All aspects.

Elevations: All elevations.

Likelihood

Likely

Expected Size

1 - 3

Valid until: Nov 29th, 2017 2:00PM