Avalanche Forecast

Issued: Mar 24th, 2019 8:00AM

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

mark herbison, Parks Canada

Glacier.

Temps at 2000m have remained above zero for the past 7 days resulting in poor overnight recovery and a isothermal snowpack at lower elevations.If the sun shines today, the avalanche hazard will increase rapidly as the upper snowpack loses strength.

Summary

Weather Forecast

Temperatures and freezing levels remain higher than expected and have kept avalanche hazard elevated at lower elevations. A mix of sun and cloud today with an alpine high of 0, light ridge top winds and a freezing level reaching 2000m. Temps slowly cooling off over the next few days with snow forecasted for Tuesday (5cm).

Snowpack Summary

High freezing levels all week have resulted in poor overnight recovery of the snow surface. Expect to find a breakable crust in the morning on all aspects at and below tree line and for the crust to break down into moist snow by the afternoon. Isothermal conditions exist below tree line. Cool dry snow exists on high Northerly aspects

Avalanche Summary

The natural spring avalanche cycle has continued for 7 days and still produced several avalanches sz 2.0 - 3.0 yesterday on the steep solar aspects, originating in the alpine and running to below tree line. Multiple artillery and helicopter control missions this week produced numerous avalanches up to sz 3.0 on all aspects.

Confidence

Timing or intensity of solar radiation is uncertain

Problems

Loose Wet

A freezing level up to 2000m and a chance of strong solar input could rapidly destabilize the upper snowpack, resulting in loose wet avalanches during the heat of the day.

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

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

Elevations: All elevations.

Likelihood

Possible - Likely

Expected Size

1 - 3

Persistent Slabs

At tree-line and above, a 40cm soft slab has bonded poorly to the underlying facets. This problem is most likely to be found on Northerly aspects in the alpine.

Avoid steep convexities or areas with a thin or variable snowpack.Pay attention to overhead hazards like cornices which could trigger the persistent slab.

Aspects: North, North East, North West.

Elevations: Alpine, Treeline.

Likelihood

Possible

Expected Size

1.5 - 3

Valid until: Mar 25th, 2019 8:00AM