Avalanche Forecast

Issued: Mar 22nd, 2015 8:12AM

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

ali haeri, Parks Canada

Glacier.

Lots of recent new snow and rain with many reports of touchy avalanche conditions. Pay close attention to any solar radiation we may receive later today as it will likely induce natural avalanche activity.

Summary

Weather Forecast

Unsettled weather for the next few days. Mostly cloudy this morning with light flurries/rain with possible clearing later today. Freezing levels are expected to rise to 1550m. Similar weather for tomorrow but with slightly cooler temperatures. Alpine winds are forecast to stay light for today and tomorrow.

Snowpack Summary

40-45cm of recent storm snow above 1800m, much of that fell as rain below that elevation. The upper snowpack is a complex mix of crusts, facetted snow and surface hoar which have been reactive to skier triggering as slab and loose avalanches. Below 1900m the top 40cm of the snowpack is moist.

Avalanche Summary

Yesterday there was a small natural avalanche cycle, numerous avalanches to size 3 in the highway corridor east of the Rogers Pass summit. Backcountry user reported very touchy conditions just west of the Park below 2000m releasing avalanches 30-60cm deep. 2 days ago, a field team ski cut moist avalanches to size 2 running far on Grizzly Shoulder.

Confidence

Problems

Storm Slabs

40-50cm of heavy storm snow will need some time to settle out and to bond to the crusts over which it lies. The associated winds were steady yesterday through the overnight period, creating soft slabs in exposed areas.

Avoid freshly wind loaded features.Be cautious as you transition into wind affected terrain.

Aspects: All aspects.

Elevations: Alpine, Treeline.

Likelihood

Possible - Likely

Expected Size

1 - 2

Loose Wet

Lower elevations were saturated with rain over the last few days. Loose wet avalanches, gaining more mass than expected, have been easily triggered by backcountry riders in the area. Any solar radiation today will further increase this risk.

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

Aspects: All aspects.

Elevations: All elevations.

Likelihood

Possible - Likely

Expected Size

1 - 3

Persistent Slabs

The upper snowpack is complex with a multitude of crusts, weak facetted layers, and surface hoar. There have been reports of skier triggered slab avalanches failing down 30-60cm on these crusts from neighboring areas.

Choose well supported terrain without convexities.Be aware of the potential for large, deep avalanches.

Aspects: All aspects.

Elevations: Alpine, Treeline.

Likelihood

Possible

Expected Size

2 - 3

Valid until: Mar 23rd, 2015 8:00AM