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Avalanche Forecast

Feb 1st, 2017–Feb 2nd, 2017
Alpine
2: Moderate
The avalanche danger rating in the alpine will be moderate
Treeline
2: Moderate
The avalanche danger rating at treeline will be moderate
Below Treeline
1: Low
The avalanche danger rating below treeline will be low
Alpine
2: Moderate
The avalanche danger rating in the alpine will be moderate
Treeline
2: Moderate
The avalanche danger rating at treeline will be moderate
Below Treeline
1: Low
The avalanche danger rating below treeline will be low
Alpine
3: Considerable
The avalanche danger rating in the alpine will be considerable
Treeline
2: Moderate
The avalanche danger rating at treeline will be moderate
Below Treeline
1: Low
The avalanche danger rating below treeline will be low

Regions: North Columbia.

Touchy winds slabs are lurking below ridgecrests and behind terrain features. Use extra caution as you transition into wind affected terrain and watch for signs of recent wind loading.

Confidence

Moderate - Wind effect is extremely variable

Weather Forecast

THURSDAY: Mainly sunny with light northeasterly winds. Freezing levels in valley bottoms with alpine temperatures reaching -15 C.FRIDAY: Increasing cloudiness with light snow flurries starting in the afternoon/evening. Light but gusty southwesterly winds and freezing levels remaining in valley bottoms with alpine temperatures reaching -10 C.SATURDAY: Cloudy with flurries bringing  3-8cm under light but gusty southwesterly winds. Freezing levels remaining in valley bottoms with alpine temperatures reaching -10 C.

Avalanche Summary

On Sunday and Monday, several natural wind slab avalanches up to size 2.5 were observed throughout the region, some triggered by cornice falls. These avalanches occurred on most aspects and were mainly in the alpine but a few were at treeline. Slabs were typically 20-30 cm thick. On Tuesday, three separate cornice failures triggered Size 2-2.5 wind slabs on the slope below, one stepped down to a deep persistent weakness near the ground. Skiers also triggered several wind slab avalanches on Monday and Tuesday up to size 1.5. One of the avalanches was remotely triggered from 15 m away. Fresh wind slabs are expected to remain sensitive to human triggering, especially on steep and unsupported (convex) slopes. Winds have recently switched from south to north and wind slabs should be expected on all aspects in exposed terrain.In the far north of the region around Blue River and Valemount, a persistent slab problem still exists. Several large human triggered avalanches were reported early last week. Click here for more details.

Snowpack Summary

Up to 15 cm of recent snow with strong shifting winds have resulted in fresh wind slabs on a variety of aspects in wind exposed terrain. A sun crust is being reported on steep solar aspects. Surface faceting is also being reported as a result of the current cold temperatures. A persistent weakness buried mid January is now down 30-50 cm and consists of buried surface hoar in sheltered areas, and/or widespread faceted old snow. It has generally stabilized but may be sensitive to triggering in isolated areas where buried surface hoar is preserved. The mid and lower snowpack are generally well settled and stable.Another surface hoar/facet persistent weakness was buried mid-December and can now be found down 100-120 cm. It has become inactive in the south of the region, but may still be sensitive to triggers in the northern part of the region near Blue River and Valemount. It is highly recommended to investigate this layer before committing to any large, unsupported features. Read the Cariboo forecast for more information.

Avalanche Problems

Wind Slabs

Fresh wind slabs are expected to remain sensitive to human triggering, especially on steep and unsupported (convex) slopes. Winds have recently switched from south to north and wind slabs should be expected on all aspects in exposed terrain.
Avoid areas where the surface snow feels stiff or slabby.Use caution in lee areas. Recent wind loading has created wind slabs.

Aspects: All aspects.

Elevations: Alpine, Treeline.

Likelihood: Possible

Expected Size: 1 - 2