Avalanche Forecast

Issued: Jan 14th, 2022 4:00PM

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

Avalanche Canada bchristie, Avalanche Canada

Email

Avoid thin, rocky start zones and convex rolls, and steep features below treeline. 

Windslabs remain sensitive to rider traffic, and rain at low elevations could rapidly change conditions for the worse.

Summary

Confidence

Moderate - Uncertainty is due to the limited number of field observations. Uncertainty is due to difficult to forecast freezing levels.

Weather Forecast

Friday Night: Mostly cloudy. 0-5 cm of snow expected. Strong southwest wind trending to extreme at higher elevations, possibly above 100 km/h. Freezing level around 1000-1200 m.Closer to 500 m in the north end of the region.

Saturday: Mostly cloudy. 5-10 cm of snow expected. Strong southwest wind, trending to extreme at higher elevations, but really dropping off through the day. Freezing levels around 900 m. 

Sunday: Mostly cloudy. 5 cm of snow expected overnight, with another 0-10 through the day. Strong southwest wind, trending to extreme at higher elevations. Freezing level around 1250 m in the south end of the region, 500 m in the north. 

Monday: Scattered clouds. 0-2 centimeters of snow overnight, and a possible trace through the day. Light to moderate west winds, trending to strong northwest at higher elevations. Freezing levels dropping to 500 m or lower. Treeline temperatures back below -5 °C.

Avalanche Summary

On Thursday in the Seaton area, our Northwest field team saw a size 2, rider-triggered windslab avalanche on a northeast aspect in the alpine. The avalanche looks like it was triggered from a thin, rocky spot below a convex roll. See their Mountain Information Network (MIN) post here for photos and more details.

There were general reports around the region of small, loose avalanches on steep aspects that were facing the sun during the period of clear and warm weather.

Also on Thursday, a professional operation in the Ningunsaw area reported an explosive triggered size 3 deep persistent slab avalanche that failed on basal facets. This avalanche was on a generally northeast facing feature around treeline, and it started just below a ridge crest. 

Remember that a lack of observed avalanches does not necessarily mean that there is a lack of avalanche activity. If you are getting out in the backcountry, and have conditions information, or even just good vibes and good photos to share, consider making a post on the Mountain Information Network (MIN). 

Snowpack Summary

30-50 cm of recent storm snow and strong southwest winds continue to form reactive wind slabs in exposed areas.

Terrain below 900 m that sees moderate to heavy rainfall could become more avalanche prone due to loose-wet avalanches or an upside down upper snowpack. 

30-50 cm below the snow surface, Faceting from the prolonged cold temperatures may increase the reactivity of the recently formed wind slabs which could end up persisting for longer than normal. 

With the mild temperatures and ongoing wind, cornices are reported to be growing larger. 

The base of the snowpack is composed of crusts and weak faceted grains, particularly in thin snowpack areas. While these layers have generally gone dormant in the region, they still have the possibility of waking up with new snow load or warming, and wind slab avalanches may still have the potential to step down to these deeper layers in isolated areas. 

Terrain and Travel

  • Stay off recently wind loaded slopes until they have had a chance to stabilize.
  • Avoid steep convexities or areas with a thin, rocky, or variable snowpack.
  • Stay in tune with the physical environment, conditions may change throughout the day.
  • Extra caution for areas experiencing rapidly warming temperatures for the first time.

Problems

Wind Slabs

An icon showing Wind Slabs

Moderate to strong southwest wind is continuing wind slab formation in exposed terrain. 

These slabs may overlie a weak faceted surface from the extended cold period and could remain reactive to human triggering for longer than normal. 

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

Elevations: Alpine, Treeline.

Likelihood

Likely

Expected Size

1 - 2

Loose Wet

An icon showing Loose Wet

Wet loose avalanches are possible on steep low elevation slopes if the temperature is above freezing.

In some places, rain may be following on dry snow for the first time, which can rapidly destabilize the snowpack.   

Aspects: All aspects.

Elevations: Below Treeline.

Likelihood

Possible - Likely

Expected Size

1 - 2

Valid until: Jan 15th, 2022 4:00PM