Avalanche Forecast

Issued: Feb 18th, 2020 4:00PM

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

Avalanche Canada mconlan, Avalanche Canada

Email

Recent wind has produced slabs near ridges. Slabs may also be triggered in sheltered terrain where they overly a layer of surface hoar. Solar input may make these slabs touchier.

Summary

Confidence

Moderate - Uncertainty is due to how quickly the snowpack will recover and gain strength.

Weather Forecast

TUESDAY NIGHT: Clear skies, light north wind, alpine temperature -8 C, freezing level below valley bottom.

WEDNESDAY: Clear skies, light southwest wind, alpine temperature -6 C, freezing level 1000 m.

THURSDAY: Clear skies, light to moderate southwest wind, alpine temperature -6 C, freezing level 1000 m.

FRIDAY: Clear skies, light to moderate southwest wind, alpine temperature -5 C, freezing level 1000 m.

Avalanche Summary

Many small to large (size 1 to 2) avalanches were reported in the region on Sunday and Monday, mostly being triggered by humans. Slabs near ridges were reported in alpine and treeline terrain. Slabs at and below treeline occurred on the surface hoar layer described in the Snowpack Summary.

Snowpack Summary

20 to 40 cm of snow from the weekend has consolidated into a reactive slab. At higher elevations near ridges, wind slabs have formed on predominantly north to east to south aspects. In sheltered terrain, the slab may overly a weak layer of feathery surface hoar crystals. On south aspects, sunny skies may begin to wet the snow surface during the day and form a melt-freeze crust during the cooler nights.

A few other crusts exist in the top 100 cm of the snowpack; reports suggest that the overlying snow is bonding relatively well to them.

Terrain and Travel

  • Watch for newly formed and reactive wind slabs as you transition into wind affected terrain.
  • Approach steep open slopes at and below treeline cautiously, buried surface hoar may exist.
  • Minimize exposure to steep, sun exposed slopes, especially when the solar radiation is strong.

Problems

Storm Slabs

An icon showing Storm Slabs

20 to 40 cm of snowfall over the weekend has consolidated into a slab that has been reactive to riders on all aspects. Near ridge lines, the snow has been blown around into lee terrain features. In more sheltered terrain, such as in open trees, the slab may overly a touchy layer of surface hoar. Sunny skies this week could continue to make these slabs touchy to human traffic.

Aspects: All aspects.

Elevations: All elevations.

Likelihood

Possible

Expected Size

1 - 2

Valid until: Feb 19th, 2020 5:00PM