Avalanche Forecast

Issued: Apr 20th, 2019 3:01PM

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

Avalanche Canada dsaly, Avalanche Canada

Be aware of a warming snowpack, the loose wet avalanche hazard will rise with limited overnight re-freeze and the pace at which the snowpack warms during the day. In the alpine, wind slabs may linger around steep, lee slopes and under cornices.

Summary

Confidence

Moderate - Timing or intensity of solar radiation is uncertain

Weather Forecast

SATURDAY NIGHT: Clear skies, light gusting moderate southwest wind, alpine temperature -1 C, freezing level 1600 m.

SUNDAY: Mix of sun and clouds, light southwest wind, alpine temperature -1 C, freezing level 1800 m.

MONDAY: Cloudy with alpine flurries accumulating though the day, 10-30 cm snow, moderate southwest wind, alpine temperature -2 C, freezing level 1800 m.

TUESDAY: Cloudy with isolated flurries up to 5 cm, light southwest wind, alpine temperature +1 C, freezing level 2000 m.

Avalanche Summary

On Friday morning, explosives triggered two wet loose size 2 avalanches and several size 2 cornices, in some cases the cornice triggered wet slab avalanches to size 2 on the slopes below. One natural storm slab avalanche was observed on a north aspect, the trigger was likely a cornice naturally failing and falling on the slope.

On Thursday night and into Friday, a loose wet avalanche and cornice cycle occurred in the region during the storm, producing small to large avalanches (size 1 and 2). Most of the avalanches occurred in the alpine as well as treeline.

Snowpack Summary

30 mm of precipitation fell as rain below 2000 m. A crust has developed on most aspects expect for high alpine slopes where up to 10 cm loose, dry snow accumulated. Cornices and wind slabs have developed with recent strong south winds. The snowpack below treeline is saturated and rapidly melting.

Problems

Loose Wet

An icon showing Loose Wet

Sun and warm temperatures will likely cause the new snow above 2000 m to moisten and become touchy on sun-exposed slopes, increasing the potential for loose wet avalanches.

  • Avoid terrain traps such as cliffs and gullies that increase the consequence of small avalanches.
  • Minimize overhead exposure and avoid steep slopes during periods of strong sun.

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

Elevations: Alpine, Treeline.

Likelihood

Possible

Expected Size

1 - 1.5

Wind Slabs

An icon showing Wind Slabs

Wind slabs formed from recent snow and strong southerly wind may remain touchy this weekend. Be wary of the potential for these slabs when entering lee terrain features near ridges above 2000 m.

  • Be careful with wind-loaded pockets, especially near ridge crests.
  • New cornices will be weak and could trigger wind slabs on slopes below.

Aspects: North, North East, East, West, North West.

Elevations: Alpine.

Likelihood

Possible

Expected Size

1 - 1.5

Valid until: Apr 21st, 2019 2:00PM