Avalanche Forecast
Regions: North Columbia.
We're in the time of year where you may find a different avalanche problem on every aspect and elevation. Carefully assess your local conditions.
Confidence
High - Confidence is due to a stable weather pattern with little change expected.
Weather Forecast
WEDNESDAY NIGHT: Cloudy with rain switching to snow, accumulation 5 to 10 cm, 20 to 40 km/h southwest wind, alpine temperature -8 C, freezing level 2000 m dropping to valley bottom.
THURSDAY: Mostly clear skies with no precipitation, 10 km/h south wind, alpine temperature -7 C, freezing level rising to 1500 m.
FRIDAY: Cloudy with isolated flurries, accumulation 1 to 3 cm, 10 km/h southwest wind, alpine temperature -5 C.
SATURDAY: Cloudy with isolated flurries, accumulation 1 to 3 cm, 20 km/h south wind, alpine temperature -2 C.
Avalanche Summary
The most notable avalanche on Tuesday was another persistent slab avalanche that occurred on the weak layer described in the Snowpack Summary. It occurred on a southeast aspect around 2100 m and was 30 to 50 cm deep. Although activity on this layer is decreasing, it can still be triggered by riders where it exists.
Otherwise, wet loose avalanches were observed out of steep terrain. We are expecting similar reports of widespread wet loose activity for Wednesday.
Snowpack Summary
Above around 2000 m, new snow will accumulate with strong south to westerly wind, possibly forming new wind slabs in lee terrain features. Below around 2000 m, a moist snow surface or hard melt-freeze crust will be found. The snow surface may moisten during daytime warming, particularly on sun-exposed slopes.
A weak layer may be found around 50 to 100 cm deep. The layer consists of surface hoar crystals in treeline terrain in areas sheltered from the wind and otherwise a hard melt-freeze crust associated with weak faceted grains on sun-exposed slopes (i.e., east, south, west). Check out this blog for more information. This layer continues to form a few large avalanches in the region each day, most commonly between 1800 and 2300 m on all aspects. This layer is isolated in nature so the likelihood of triggering it is low, but the consequence of doing so could be high.
There are presently no deeper concerns.
Terrain and Travel
- Potential for wide propagation exists, fresh slabs may rest on surface hoar, facets and/or crust.
- Look for signs of instability: whumphing, hollow sounds, shooting cracks, and recent avalanches.
- Watch for newly formed and reactive wind slabs as you transition into wind affected terrain.
- Minimize exposure to sun-exposed slopes when the solar radiation is strong.
- Pay attention to cornices and give them a wide berth when traveling on or below ridges.
Avalanche Problems
Persistent Slabs
A weak layer may be found around 50 to 100 cm deep. The layer consists of weak faceted grains above a hard melt-freeze crust on sun-exposed slopes and surface hoar in shaded areas sheltered from the wind. We are still receiving reports of a few avalanches a day, generally between 1800 and 2300 m on all aspects. Triggering this layer could result in a high consequence.
Aspects: All aspects.
Elevations: All elevations.
Likelihood: Possible
Expected Size: 2 - 3.5
Wind Slabs
Wind slabs may be found in steep, lee terrain features in wind-exposed terrain.
Aspects: North, North East, East, South East, North West.
Elevations: Alpine, Treeline.
Likelihood: Possible
Expected Size: 1 - 2
Loose Wet
Wet loose avalanches may be triggered out of steep terrain during periods of strong sun, particularly in the afternoon during the heat of the day.
Aspects: South East, South, South West.
Elevations: All elevations.
Likelihood: Possible
Expected Size: 1 - 2