Major warming and sun are expected to destabilize the upper snowpack over the next few days. Cornices will begin to weaken on Friday and wet loose activity is expected on steep sun exposed slopes.
Summary
Confidence
Moderate - Uncertainty is due to rapidly fluctuating freezing levels. Uncertainty is due to the timing or intensity of solar radiation and its effect on the snowpack.
Weather Forecast
A warm ridge of high pressure establishes itself over the region on Friday and is expected to bring sustained freezing levels around 3000 m with an inversion for the weekend.Â
Thursday Night: Skies clearing overnight, light to moderate NW wind, freezing levels 1200-1400 m.Â
Friday: A mix of sun and cloud, light to moderate NW wind, freezing levels climbing to around 3000 m with an inversion.Â
Saturday: A mix of sun and cloud, moderate NW wind, freezing levels around 3200 m with an inversion.Â
Sunday: A mix of sun and cloud, moderate W wind, freezing levels around 3000 m dropping to around 2000 m overnight.Â
Avalanche Summary
No new avalanche activity have been reported over the last few days.
If you head out into the mountains, please share any observations or photos on the Mountain Information Network.
Snowpack Summary
Heavy rain and warm temperatures have saturated the surface snow to mountain top elevations and a widespread crust is now expected where the snow surface has refrozen. Below this, snow is moist down 50-100 cm where several old crust are now breaking down.Â
Around 150 to 200 cm deep, sugary faceted grains may sit above a melt freeze crust, that formed during the cold spell in late December. Reports suggest that the snowpack has been bonding well to these layers. The middle and base of the snowpack are strong, consisting of well-bonded snow and various hard melt-freeze crusts.
Terrain and Travel
- The more the snow feels like a slurpy, the more likely loose wet avalanches will become.
- Avoid exposure to steep, sun exposed slopes, especially when the solar radiation is strong.
- Pay attention to cornices and give them a wide berth when traveling on or below ridges.
Problems
Loose Wet
The warming and sun are not expected to have a major impact on an already warm snowpack but wet loose avalanches should be expected from steep terrain features. Extra caution will be required around steep south facing slopes when the sun is strong.
Aspects: All aspects.
Elevations: All elevations.
Likelihood
Expected Size
Cornices
Large cornices around ridge crests are expected to become weak during the warming event this weekend. With each day of warming, cornice failures will become more likely.
Aspects: North, North East, East, North West.
Elevations: Alpine.
Likelihood
Expected Size
Valid until: Jan 21st, 2022 4:00PM
