Avalanche Forecast

Issued: Nov 23rd, 2017 4:21PM

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

Avalanche Canada jsmith, Avalanche Canada

Welcome to winter! It's that time of year when winter is slowly winding up and observations are limited. Due to limited data it is CRITICAL to supplement this information with your own observations. Please post your observations to the MIN.

Summary

Confidence

Low - Due to the number of field observations

Weather Forecast

FRIDAY: Mostly cloudy with isolated flurries, moderate southwesterly winds, freezing levels dropping to 1000m Thursday night, then rising to around 1500m. SATURDAY: Mostly cloudy with flurries, light to moderate southeasterly winds, freezing levels around 1500m. SUNDAY: 5-15cm new snow throughout the day, moderate to strong southerly winds, freezing levels rising to around 2200m.

Avalanche Summary

On Wednesday, no new avalanches were reported in this region. However, we currently have very limited observations in this region. Please submit your observations to the Mountain Information Network (MIN).

Snowpack Summary

Fresh wind slabs may have formed below alpine ridgetops in areas where the precipitation fell as snow on Thursday afternoon. The depth of the snowpack varies greatly with elevation. Recent reports suggest the average depth is 200+cm in the alpine, 100-150cm at treeline, and decreasing rapidly below treeline where the primary hazards are rocks, stumps, and open creeks. Recent heavy rain to the mountaintops has rapidly shrunk the snowpack and created a moist snowpack to the ground in many areas. (As well as very injury prone riding) The major feature in the snowpack is a crust which was formed around November 11th can be found approximately 100cm down at treeline elevations. However, freezing levels are forecasted to drop dramatically by Friday morning which will likely create a strong crust at most elevations and decrease the likelihood of triggering avalanches on the November crust. We currently have very limited snowpack observations within this region and it is critical to supplement this information with your own observations.

Problems

Wind Slabs

An icon showing Wind Slabs
Fresh wind slabs may have formed below alpine ridgetops in areas where the precipitation fell as snow on Thursday afternoon.
Avoid areas which have been loaded by new snow and wind.Be cautious as you transition into wind affected terrain.

Aspects: North, North East, East, South East.

Elevations: Alpine.

Likelihood

Possible - Likely

Expected Size

1 - 2

Persistent Slabs

An icon showing Persistent Slabs
Recent rain at most elevations combined with overnight cooling Thursday night will reduce the likelihood of triggering this layer. Areas in which the snowpack above this layer remained dry should be treated with increased caution.
Avoid shallow snowpack areas where triggering is more likely.

Aspects: All aspects.

Elevations: Alpine, Treeline.

Likelihood

Unlikely - Possible

Expected Size

2 - 3

Valid until: Nov 24th, 2017 2:00PM