Avalanche Forecast

Issued: Apr 15th, 2022 4:00PM

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

Avalanche Canada jleblanc, Avalanche Canada

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Weather and avalanche forecasts are conducive for great mountain adventures, but be wary of pockets of wind slabs and cornices. Heading into the backcountry this weekend ? Please consider filling out a MIN to report local conditions ! 

Summary

Confidence

Moderate - Uncertainty is due to the limited number of field observations.

Weather Forecast

Not much change as the broad upper trough is still in place. Cool and unstable conditions, combined with daytime heating, will likely give scattered flurries across the southern part of the province. Warmer and closer to seasonal temperatures will arrive on Sunday and Monday.

FRIDAY NIGHT: Cloudy skies / scattered flurries / light variable wind / treeline low around -10 C / freezing level to valley bottom.

SATURDAY: Mainly sunny with increasing cloudiness late afternoon / easterly wind increasing to 20-40 km/h / treeline high of -5 C / freezing level rising to 1500 m / overnight localized accumulations 5-10 cm with freezing level returning to valley bottom.

SUNDAY: Partially cloudy / localized snow accumulations 3-5 cm / light to moderate southwest wind / treeline high around -3 C / freezing level rising to 1500 m. 

MONDAY: Mix of sun and clouds / light to moderate southerly wind / treeline high around 0C / freezing level rising to 1800 m.

Avalanche Summary

Observations are very limited this time of year. Small loose wet avalanches (size 1) were observed on steep rocky terrain features near Crowsnest due to strong solar input. Check out the South Rockies field team's MIN from Friday for pictures of current conditions ! 

Snowpack Summary

Over the past few days, eastern upslope areas of the region received light snow flurries accumulation each day from the storm system impacting the Prairies (up to 20 cm). Recent periods of strong wind from the northeast through southeast have redistributed the recent snow in exposed high elevation terrain forming small pockets of wind slabs which may still be reactive, especially in the east of the region. A widespread and supportive melt-freeze crust which formed during the major warming event on April 8 is found under the recent snow and / or wind slabs. The middle and lower snowpacks are currently well settled and strong.

Terrain and Travel

  • Be careful as you transition into wind affected terrain.
  • Cornices often break further back than expected; give them a wide berth when traveling on ridgetops.
  • When a thick, melt-freeze surface crust is present, avalanche activity is unlikely.

Problems

Wind Slabs

An icon showing Wind Slabs

Recent winds from the northeast through southeast have redistributed the 10-15 cm snowfall into small wind slabs in exposed terrain features and immediate lee of ridges. Solar aspects are features of concern where these slabs are poorly bonded to the previous surface due to weak faceted grains that have developed over a thick and supportive melt-freeze crust.

Aspects: North, South, South West, West, North West.

Elevations: Alpine.

Likelihood

Unlikely - Possible

Expected Size

1 - 1.5

Cornices

An icon showing Cornices

Cornices have grown large recently but are generally not expected to fail naturally with the current abd forecasted conditions. However, human-triggered cornices are possible so give them a wide berth when travelling on ridges and watch for signs that they may be weakening if they are exposed to extended periods of sun. 

Aspects: All aspects.

Elevations: Alpine.

Likelihood

Possible

Expected Size

2 - 3

Valid until: Apr 16th, 2022 4:00PM