Avalanche Forecast

Issued: Feb 19th, 2020 5:00PM

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

Avalanche Canada JSmith, Avalanche Canada

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Intense solar radiation can rapidly change conditions. Avoid slopes that are threatened by large cornices overhead during the heat of the day.

Summary

Confidence

Moderate - Uncertainty is due to limitations in the field data.

Weather Forecast

WEDNESDAY NIGHT: Clear, light southwest wind, alpine temperature -12 C, freezing level below valley bottom.

THURSDAY: Sunny, light to moderate southwest wind, alpine temperature -5 C, freezing level 1000 m.

FRIDAY: Increasing cloudiness, moderate southwest wind, alpine temperature -4 C, freezing level 1200 m.

SATURDAY: 5-10 cm snow, moderate west wind, alpine temperature -7 C, freezing level 800 m.

Avalanche Summary

A cornice triggered size 3 deep persistent slab avalanche was reported on a steep convexity at treeline on Tuesday. There has been limited avalanche activity reported over the long weekend, suggesting storm slabs are becoming less reactive. On Monday a few small (size 1) storm slabs were reported by riders on a variety of aspects. Looking forward, slab avalanches may remain possible to trigger, especially on sun-exposed and wind loaded slopes.

Snowpack Summary

Last week it snowed 40-80 cm, with the greatest accumulations in the northern part of the region. This snow has shown signs of settling and gaining strength over the past few days, with the exception of some wind affected slopes. This recent snow sits above a few different interfaces (a hard rain crust below 1800 m, sun crusts on south-facing slopes, and potentially small surface hoar at treeline), but appears to be bonding well to these interfaces. Sunny weather this week could weaken cornices and surface snow on steep south-facing slopes. The mid and lower snowpack are generally well settled and strong.

Terrain and Travel

  • Be alert to conditions that change with elevation and wind exposure.
  • Avoid exposure to steep, sun exposed slopes, especially when the solar radiation is strong.
  • Watch for signs of instability like whumpfing, hollow sounds, shooting cracks or recent avalanches.

Problems

Storm Slabs

An icon showing Storm Slabs

Storm slab avalanches are possible to trigger on wind loaded or steep convex slopes, and may release naturally on sun-exposed slopes in the heat of the day.

Aspects: All aspects.

Elevations: All elevations.

Likelihood

Possible

Expected Size

1 - 2

Valid until: Feb 20th, 2020 5:00PM