Avalanche Forecast

Issued: Mar 5th, 2016 9:16AM

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

Avalanche Canada jlammers, Avalanche Canada

Forecast snowfall amounts for Saturday night vary greatly across the region. If more than 20cm falls in your riding area, the Avalanche Danger in the alpine may be HIGH.

Summary

Confidence

Moderate - Forecast snowfall amounts are uncertain on Sunday

Weather Forecast

On Saturday night expect 10-15cm of new snow with another 10cm falling on Sunday. A mix of sun and cloud is forecast for Monday while light snowfall is expected on Tuesday. Winds should be extreme and southwesterly on Sunday, becoming mainly light on Monday and Tuesday. Freezing levels should hover between 1300 and 1500m for the forecast period.

Avalanche Summary

Backcountry observations have been limited because of inclement weather, but I suspect there was a round of storm slab activity in response to new snow and wind on Friday night. Of note, an isolated yet destructive size 3 natural persistent slab avalanche was reported this week in the South Chilcotin area north of Goldbridge. The avalanche failed on surface hoar buried in early February. Cornices are large and fragile, and may also fail under the weight of a person.

Snowpack Summary

Continued moderate snowfall and strong southerly winds have formed reactive storm slabs on lee and cross-loaded alpine and treeline features. The upper snowpack sits above a crust that was reported on all aspects and elevations with isolated pockets of surface hoar in high north facing terrain that stayed cool prior to the storm. The mid and lower snowpack are generally well settled. That said, a layer of surface hoar buried at the beginning of February is a concern in the South Chilcotin area and can be found about 80cm below the surface. Although this layer is isolated, it has been responsible for destructive natural avalanche activity and is worth keeping on your radar if you're headed to the north of the region.

Problems

Storm Slabs

An icon showing Storm Slabs
Continued stormy weather on Sunday will promote ongoing storm slab activity. Forecast extreme winds will encourage hard slab formation and wide propagations.
Be aware of the potential for wide propagations due to the presence of hard windslabs.>Be cautious as you transition into wind affected terrain.>

Aspects: All aspects.

Elevations: All elevations.

Likelihood

Likely

Expected Size

1 - 3

Cornices

An icon showing Cornices
Cornices are reported to be very large and weak. Stay well back from ridgecrests, and watch your overhead hazard as a cornice fall could trigger a large avalanche on the slope below.
Cornices become weak with daytime heating. >Extra caution needed around cornices with current conditions.>

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

Elevations: Alpine, Treeline.

Likelihood

Possible

Expected Size

1 - 4

Valid until: Mar 6th, 2016 2:00PM