Avalanche Forecast

Issued: Apr 2nd, 2014 8:00AM

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

chris gooliaff, Parks Canada

Glacier.

Sunshine has a dramatic effect on the snowpack at this time of year, warming and weakening it very quickly.

Summary

Weather Forecast

High overcast will spread through the area, bringing scattered flurries and reducing the overall punch of the sun today. A more organized front will arrive Thursday, bringing as much as 20mm of precipitation, with freezing levels at 1400m and moderate to strong westerly winds. Winter ain't over yet...

Snowpack Summary

Temperature crust on solar aspects, the Mar 22 down ~ 30-50cm, the Mar 13 crust down 75cm, the Mar 2 down 1-1.5m. On north aspects the upper snowpack consists of settling storm snow to about 1600m below which there will be a crust. The Feb 10 surface hoar crust layer is down 2m.

Avalanche Summary

As expected, the warm temperatures and high solar input created numerous moist, loose avalanches up to size 2.5 on S and W aspects yesterday, mainly at tree-line or below. On Monday, there was a skier controlled avalanche, size 1.5 on an immediate lee feature of a ridge top, Nw asp, 2420m, down 20cm on the March 22 crust, 100m long and 25m wide.

Confidence

Problems

Loose Wet

The April sunshine is strong. If it pokes through the clouds today, expect solar aspects to destabilize quickly, especially at lower elevations.

Avoid sun exposed slopes when the solar radiation is strong, especially if snow is moist or wet.Watch for clues, like sluffing off of cliffs, that the snowpack is warming up.

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

Elevations: All elevations.

Likelihood

Possible - Likely

Expected Size

1 - 2

Persistent Slabs

There are numerous sliding layers buried in the upper 1-1.5m of the snowpack. If we see any strong sunshine today, there could be avalanches stepping down to these layers.

Avoid shallow snowpack areas where triggering is more likely.Travel early before the heat of the day, and avoid big slopes in the afternoon.

Aspects: All aspects.

Elevations: Alpine, Treeline.

Likelihood

Possible

Expected Size

2 - 3

Cornices

The spring-time cornices are large and looming overhead. They weaken with sunshine and warming temperatures, so plan your day to be away from them as things warm up.

Cornices become weak with daytime heating, so travel early on exposed slopes.

Aspects: All aspects.

Elevations: Alpine.

Likelihood

Possible

Expected Size

1 - 3

Valid until: Apr 3rd, 2014 8:00AM