Avalanche Canada cgarritty, Avalanche Canada

Lizard Range and Flathead Avalanche Forecast

Jan 10th, 2020 4:00PM

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

Strong winds are maintaining elevated avalanche danger and light new snow amounts will feed our wind slab problem. Tune in to local wind patterns and seek out sheltered low density snow for the best, safest skiing and riding.

Summary

Confidence

High -

Weather Forecast

Friday night: Cloudy with scattered flurries bringing about 5 cm of new snow. Strong southwest winds, easing into the morning.

Saturday: Cloudy with continuing flurries and another 5 cm of new snow, increasing a bit overnight. Light to moderate southwest winds increasing in the evening. Alpine high temperatures around -7.

Sunday: Mainly cloudy with isolated flurries and a trace to 5 cm of new snow, increasing overnight. Light to moderate south winds. Alpine temperatures falling to about -15.

Monday: Mainly cloudy with easing flurries and a trace of new snow. Light to moderate southwest winds. Alpine high temperatures falling again to about -19.

Avalanche Summary

Reports of avalanche activity in the Fernie area on Wednesday and Thursday showed a continuation of Tuesday's conditions, with explosives control yielding numerous storm slab release from size 2 (arge) to size 3 (very large). Notably, two larger results involved the weak basal snowpack by either stepping down to this layer or failing on its reloaded surface.

Tuesday's reports showed numerous storm slabs releasing naturally as well as with remote triggers from skier traffic, and with explosives. Avalanches ranged from size 1 to size 2.. The bulk of this activity was observed on north to east aspects.

Looking forward, the recent snow should begin to form a more reliable bond with the old surface as our slab problems become increasingly limited to wind-loaded areas.

Snowpack Summary

The recent storm brought about 40-70 cm of new snow to the region over the early part of the week. Much of this snow has been wind-affected or redistributed into new wind slabs by recent southwest winds. For the most part, the interface below the new snow consists of old wind-affected snow.

Several crusts layers exist in the mid to upper snowpack as a result of recent warming and rain events. These have not been identified as bed surfaces or failure planes in recent avalanche activity.

The bottom 10-20 cm of the snowpack consists of weak faceted snow and decomposing crusts. Although inherently weak, this basal layer has not been an active avalanche problem in our region for several weeks.

Terrain and Travel

  • Avoid freshly wind loaded terrain features.
  • Keep your guard up at lower elevations. Wind slab formation has been extensive.

Problems

Wind Slabs

An icon showing Wind Slabs

Likelihood

Possible-Likely

Expected Size

1 - 2

Recent winds have redistributed much of our new snow into reactive slabs at all elevations and on a wide range of aspects. Strong southwest winds promoted aggressive slab formation on Friday.

Aspects:

North, North East, East, South East, North West.

Elevations:

All elevations.

Valid until: Jan 11th, 2020 5:00PM