Avalanche Forecast
Regions: Tutshi, Wheaton, White Pass East, White Pass West, Yukon.
Start with small slopes, and watch for signs of instability like shooting cracks as you move into wind-exposed terrain.
Be cautious as you gather information after this warm, stormy period.
Confidence
Low
Avalanche Summary
A widespread, natural avalanche cycle up to size 2.5 likely occurred on all aspects through the warm and stormy period this weekend.
Looking forward to Wednesday, we expect that human-triggered avalanches will be likely anywhere that wind is redistributing dry snow into thicker, more reactive slabs, potentially over a hard, slippery crust. North and east-facing features are currently the most likely to be wind-loaded.
Snowpack Summary
Storm snow totals around 35-50 cm by the end of the day Tuesday.
Freezing levels were up to 1700 m over the weekend but they have started to drop, resulting in a frozen crust or wet snow at the surface, or under fresh, dry snow.
Strong southerly alpine winds have likely formed touchy slabs at upper elevations on north and east facing terrain.
A buried weak layer of surface hoar and facets has been found in isolated locations 45-70 cm below the surface. There is potential for the recent precipitation and warm temperatures to overload this layer triggering large avalanches.
Weather Summary
Tuesday Night
Partly cloudy. No new snow expected. Strong southwest ridgetop wind. Treeline temperature around -10°C.
Wednesday
Increasing cloud through the day. 1-2 cm of snow expected. Light variable ridgetop wind. Treeline temperature around -12°C.
Thursday
Mostly cloudy. 5-10 cm of snow expected. Light south or southwest ridgetop wind. Treeline low around -17 °C.
Friday
Partly cloudy. 1-2 cm of snow expected. Light southwest ridgetop wind. Treeline low around -25 °C.
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.
- Back off if you encounter whumpfing, hollow sounds, or shooting cracks.
- Wind slabs may be poorly bonded to the underlying crust.
- When a thick, melt-freeze surface crust is present, avalanche activity is unlikely.
Avalanche Problems
Wind Slabs
Moderate to strong southwest wind is likely redistributing recent storm snow into reactive wind slabs on north and east facing terrain. These slabs also may not be bonding to a crust that formed as temperatures dropped.
Aspects: North, North East, East, South East, North West.
Elevations: Alpine, Treeline.
Likelihood: Likely
Expected Size: 1 - 2.5