Avalanche Forecast

Issued: Mar 21st, 2016 10:13AM

The alpine rating is moderate, the treeline rating is moderate, and the below treeline rating is low. Known problems include Wind Slabs, Cornices and Loose Wet.

jlammers, Avalanche Canada

South Coast.

Posted Danger Ratings are for the northern part of the region. A storm may pass through the Coquihalla area on Monday night and Tuesday. Pay close attention to local weather conditions and be prepared to back off to simple terrain.

Summary

Confidence

Moderate - Forecast snowfall amounts are uncertain on Tuesday

Weather Forecast

On Tuesday expect generally overcast skies with isolated flurries. On Wednesday a Pacific system will bring 5-15cm of new snow to the region. Light flurries are forecast for Thursday. Ridgetop winds will be light on Tuesday, and then become moderate and southwesterly with Wednesday's precipitation. Freezing levels should hover between 1200 and 1300m for the forecast period.

Avalanche Summary

No new avalanches have been reported, but this may speak more to a lack of observations rather than actual conditions.

Snowpack Summary

On Sunday night the region received up to 15cm of new snow with highest amounts falling in the northern parts of the region (areas accessed from the Pemberton Valley). Further south in the Coquihalla area, it rained to ridgetop and depending on the current temperature, surfaces are either moist or refrozen. Where it did snow, moderate southerly winds formed soft slabs which seemed most reactive in lee alpine terrain. The new snow overlies a sun crust on sun-exposed slopes, dry settled powder on shady slopes and moist snow below 1800m. Below the new snow the snowpack is strong and well-settled throughout with no notable persistent weaknesses. Cornices are huge and fragile.

Problems

Wind Slabs

Snow accumulations from Sunday are expected to strengthen rather quickly. That said, wind slabs may remain sensitive to human triggering in high elevation, wind-exposed terrain. In the Coquihalla area, ongoing storm loading is possible on Tuesday.

Stay off recent wind loaded areas until the slope has had a chance to stabilize.>Be cautious as you transition into wind affected terrain.>

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

Elevations: Alpine, Treeline.

Likelihood

Possible

Expected Size

1 - 3

Cornices

Some cornices are larger than a bus, and could easily collapse under the weight of a person, or with daytime warming. Give these monsters a wide berth when traveling on or below ridge crests.

Give cornices a wide berth when travelling on or below ridges.>Extra caution needed around cornices with current conditions.>

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

Elevations: Alpine.

Likelihood

Possible

Expected Size

1 - 5

Loose Wet

Brief periods of solar radiation are possible on Tuesday. If this happens, pushy loose wet avalanches will become a concern in sun-exposed terrain.

Avoid sun exposed slopes when the solar radiation is strong, especially if snow is moist or wet.>

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

Elevations: All elevations.

Likelihood

Possible

Expected Size

1 - 3

Valid until: Mar 22nd, 2016 2:00PM