Avalanche Forecast

Issued: Nov 25th, 2013 9:00AM

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

ghelgeson, Avalanche Canada

South Rockies.

Check out the South Rockies Blog for thoughts on early season forecasting in this region. If you have recent observations please send them to forecaster@avalanche.ca

Summary

Confidence

Poor - Due to the number of field observations

Weather Forecast

Synopsis: The current pattern persists through the forecast period. On Wednesday a weak frontal system should clear out the inversion. No significant change in the weather for the forecast period.Tuesday: Freezing Level: Near 0 C at Valley Bottom, above freezing layer from 1500 - 3000m. Precip: No significant precip expected. Wind: Light SWWednesday: Freezing Level: 1200m Precip: No significant precip expected. Wind: Light, Variable.Thursday: Freezing Level: Valley Bottom Precip: No significant precip expected. Wind: Light, SW switching to Moderate W in the late afternoon.

Avalanche Summary

The last reported avalanche activity was during the tail end of the storm on Tuesday Nov 19th. If you see or trigger an avalanche, please send us a note at: forecaster@avalanche.ca

Snowpack Summary

Observations from this region are EXTREMELY limited at the moment!Treeline snowpack depths in sheltered areas vary between approximately 40-80 cm. Since the snow stopped falling on Nov 19th it has been subjected to strong wind, cold temps and chinook driven warming. As a result it should be easy to find wind scoured snow, old windslabs, temperature crusts & facet formation in a single day's ride or tour.A crust or significant density change may exist around 40 cm below the surface. This has been reported to have weak faceted crystals above and below, and produces sudden "pop" results in compression tests. Below this near the base of the snowpack, an earlier crust buried in October lies close to the ground. This layer may still be of concern on isolated smooth terrain features that have not seen avalanche activity.

Problems

Persistent Slabs

Smooth alpine slopes that did not previously slide are still of concern. With very little data on the current conditions, I would treat all slopes as suspect until proven otherwise.

Be aware of thin areas that may propogate to deeper instabilites.>Carefully evaluate big terrain features by digging down and testing on adjacent, safe slopes before committing to a line.>

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

Elevations: Alpine.

Likelihood

Unlikely - Possible

Expected Size

1 - 3

Wind Slabs

The region has seen a lot of wind in the last week. If an open line at and above treeline looks good enough to ski or ride the feature may be wind loaded.

Be careful with wind loaded pockets.>Be cautious as you transition into wind affected terrain.>Use ridges or ribs to avoid pockets of wind loaded snow.>

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

Elevations: Alpine, Treeline.

Likelihood

Unlikely - Possible

Expected Size

1 - 3

Valid until: Nov 26th, 2013 2:00PM