Avalanche Forecast

Issued: Mar 15th, 2015 9:08AM

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

bcorrigan, Avalanche Canada

Northwest Inland.

Large amounts of new snow have fallen in the region. Careful route and terrain selection is essential to safe back country riding.

Summary

Confidence

Fair - Due to the number and quality of field observations

Weather Forecast

The Northwest Inland should have sunny skies until the next Pacific system arrives on Thursday. Freezing levels will be at valley bottoms overnight and between 1000 and 1500M during the day.

Avalanche Summary

There are numerous reports of large avalanches up to size 4 from yesterday.Â Commercial operators and Min. of Highways have reported evidence of a large natural cycle thatÂ occurred during or towards the end of this last storm..

Snowpack Summary

The amount of storm snow varies from 20 to 125cmÂ across the Inland Northwest region with the largest amounts bing farther north and west. Below the new snow surface, there are a variety of old interfaces;Â Wind slabs, hard crusts, surface hoar, and/or surface facets. At the base of the snowpack, weak facets may be found and could possibly be triggered with a big enough load such as a cornice failure. In other parts of the province there has been a surge in activity recently on old, buried weak layers that may be attributed to the rapid warming event that just occurred. These old deeply buried layers could produce very large destructive avalanches if they are triggered. Cornices are now getting to be large and potentially unstable. Solar aspects are now a concern, especially in the afternoon.

Problems

Storm Slabs

Up to 125cm of new snow has fallen in the past 48 hrs in parts of the region. The storm was accompanied by strong winds and warm temperatures., classic conditions for producing large destructive avalanches.

The new snow will require several days to settle and stabilize.>Avoid all avalanche terrain during periods of heavy loading from new snow, wind, or rain.>

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

Elevations: Alpine, Treeline.

Likelihood

Likely

Expected Size

1 - 4

Wind Slabs

Buried wind slabs should begin to bond with the new snow that fell recently.

Avoid steep slopes below cornices.>Use ridges or ribs to avoid pockets of wind loaded snow.>Be cautious as you transition into wind affected terrain.>

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

Elevations: All elevations.

Likelihood

Possible - Likely

Expected Size

1 - 4

Valid until: Mar 16th, 2015 2:00PM