Avalanche Forecast
Issued: Feb 13th, 2023 4:00PM
The alpine rating is , the treeline rating is , and the below treeline rating is Known problems include Wind Slabs.
lbaker,
Avalanche Canada
Dangerous avalanche conditions exist in the alpine where storm snow and strong winds have built fresh wind slabs.
Be alert to conditions that change with aspect and elevation, especially on slopes being impacted by direct sun. Periods of intense solar radiation could quickly initiate a natural avalanche cycle.
Summary
Confidence
High
Avalanche Summary
On Monday afternoon, search and rescue technicians responded to a fatal avalanche incident north of the Sea to Sky region. The avalanche is believed to have occurred on Saturday and was initiated in a shallow rocky area. See the MIN for more details.
Poor visibility through the weekend kept most operators from seeing into higher elevations. On Saturday, a small cornice chunk was reported to have triggered a size 1 wind slab avalanche.
On Friday, wind slab avalanches were reported to be reactive to natural and human triggers. A size 1.5 skier remote avalanche was triggered from 10 m away on a west aspect at 1700 m. See MIN for details and photos. A cornice triggered a size 2 avalanche on a northeast slope in the alpine. These are both good reminders to use extra caution as you are transitioning into wind-affected terrain and be aware of the overhead hazard.
Please continue to share any observations or photos on the Mountain Information Network.
Snowpack Summary
10-20 cm of recent storm snow overlies 60-80 cm of wind-affected snow and a crust at lower elevations. A melt-freeze crust is found down 50-80 cm and has been reactive in test pits however we have not seen recent avalanches on this layer.
The snowpack in this region is generally weak and shallow with sugary snow near the base. Avoid areas where snowpack depth varies rapidly like thin rocky start zones. Snowpack depths around treeline range between 150 to 250 cm.
Weather Summary
Monday Night
Cloudy with lingering convective flurries, 1-5 cm accumulation. West winds switch to the north 20 km/h. Treeline temperature -10 °C. Freezing levels drop from 1000 m to valley bottom.
Tuesday
Mix of sun and cloud. Winds north northwest 10 to 15 km/h. Treeline temperature -8 °C. Freezing level 800 m.
Wednesday
Mainly sunny with clouds increasing in the afternoon. Winds west 10 to 25 km/h. Treeline temperature -10 °C. Freezing level 600 m.
Thursday
Mix of sun and cloud with isolated flurries, trace accumulation. Winds southwest 25 km/h gusting to 40 km/h. Treeline temperature -8 °C. Freezing level 800 m.
More details can be found in the Mountain Weather Forecast.
Terrain and Travel Advice
- Watch for newly formed and reactive wind slabs as you transition into wind affected terrain.
- Avoid steep, rocky, and wind effected areas where triggering slabs is more likely.
- Avoid exposure to overhead hazards when solar radiation is strong.
Problems
Wind Slabs
10-20 cm of recent storm snow has been redistributed by strong southwest winds into fresh wind slabs. Slabs will likely be the deepest and most reactive on north and east aspects at treeline. Wind slabs may be sitting on a crust making them especially reactive to ridder triggering.
Monday night winds switch to light winds from the north. Watch for winds reverse-loading exposed features at higher elevations as you travel through terrain tomorrow.
During periods of direct sun watch for slab properties increasing in surface snow. Minimize exposure to steep sun-exposed slopes, especially when solar radiation is strong.
Aspects: All aspects.
Elevations: Alpine, Treeline.
Likelihood
Expected Size
Valid until: Feb 14th, 2023 4:00PM
