Avalanche Forecast

Issued: Mar 21st, 2019 8:00AM

The alpine rating is high, the treeline rating is high, and the below treeline rating is high. Known problems include Loose Wet and Persistent Slabs.

chris gooliaff, Parks Canada

Glacier.

http://www.pc.gc.ca/apps/links/goto_e.asp?destination=The sun continues to scorch the Rogers Pass area, creating dangerous avalanche conditions in the heat of the day. Travel in avalanche terrain is not recommended.

Summary

Weather Forecast

Warm again today, with alpine temps around 6*C, light winds, and intense sunshine. Freezing levels (FZL) hover around 3200m today. Friday will be a mix of sun and clouds, FZL around 3100m, and alpine highs of 5*C. Clouds roll in on the weekend, with freezing levels dropping to 1900m and ~10cm of snow on Sunday.

Snowpack Summary

A ~40cm slab exists at alpine and tree-line elevations, while isothermal conditions are present below tree-line. Surface crusts of varying hardness are prevalent on all but true North aspects in the Alpine. A THIRD night in a row of above freezing temps at tree-line elevation has prevented a solid crust from forming at 2000m and above.

Avalanche Summary

A natural spring avalanche cycle started Sunday producing loose wet avalanches and slab avalanches to size 3. Much of the surface slabs have already avalanched. However, with no re-freeze overnight, above average temperatures, and strong solar input, the cycle will continue. A group of 4 skiers triggered a sz 2 ascending to Mt Green, on Sunday.

Confidence

Problems

Loose Wet

Strong sunshine and rapidly increasing temps will destabilize the upper snowpack, resulting in loose wet avalanches during the heat of the day. Traveling in avalanche terrain is not recommended today, especially on solar aspects this afternoon.

Avoid slopes when the solar radiation is strong, especially if they have large cornices overhead.Minimize exposure to steep, sun exposed slopes when the solar radiation is strong.

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

Elevations: All elevations.

Likelihood

Very Likely - Certain

Expected Size

1.5 - 3.5

Persistent Slabs

At tree-line and above, a ~40cm soft slab is bonding poorly to the underlying sun crust, or to facets on shaded aspects. The prolonged warmth has helped the mtns shed much of the slab, so where it still exists, be wary of its unstable nature.

Convex features and steep unsupported slopes will be most prone to triggering.Pay attention to overhead hazards like cornices which could trigger the persistent slab.

Aspects: All aspects.

Elevations: Alpine, Treeline.

Likelihood

Likely

Expected Size

2 - 3

Valid until: Mar 22nd, 2019 8:00AM