Archived

Avalanche Forecast

Feb 6th, 2015–Feb 7th, 2015

Alpine

4: High

The avalanche danger rating in the alpine will be high

Treeline

3: Considerable

The avalanche danger rating at treeline will be considerable

Below Treeline

2: Moderate

The avalanche danger rating below treeline will be moderate

Alpine

3: Considerable

The avalanche danger rating in the alpine will be considerable

Treeline

3: Considerable

The avalanche danger rating at treeline will be considerable

Below Treeline

2: Moderate

The avalanche danger rating below treeline will be moderate

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

2: Moderate

The avalanche danger rating below treeline will be moderate

Regions: South Rockies.

Avalanche danger is high due to loading from new snow or rain, and wind.

Confidence

Fair - Intensity of incoming weather systems is uncertain

Weather Forecast

The Pineapple Express which has been bringing lots of moisture and warm temperatures over the Southern part of BC will continue to spread moderate to heavy precipitation until the end of the day Saturday, taper off on Sunday and pick up again on Monday as another storm passes through. Freezing levels are expected to hover between 1700m and 2000m and winds to blow moderate to strong from the southwest on Saturday. Freezing levels should to start lowering again by Sunday.

Avalanche Summary

Natural and skier triggered moist and wet slab avalanches up to size 2 were reported on Friday in the alpine and at treeline. These would have failed within the storm snow.

Snowpack Summary

The ~30 cm recent storm snow is now either wet under 1800m or moist above. Strong winds from the southwest have built thick, touchy wind slabs on east and northeast facing alpine slopes. The sustained rain forecast up to ~1900m through Saturday will continue to break down the late January crust, increasing the possibility of avalanches stepping down to deeper weak layers. Avalanche danger will therefore stay high and traveling in the backcountry will remain very dangerous. The mid-December crust/facet/surface hoar combo is found down 50-95 cm and could come out of its dormant stage making for some very large avalanches.

Avalanche Problems

Storm Slabs

Expect heavy snow to keep accumulating in the alpine adding load to the current storm slab and wind slabs to keep developing on North and NorthEast facing slopes.

Reduce your exposure to runout zones.>

Aspects: All aspects.

Elevations: Alpine.

Likelihood: Very Likely

Expected Size: 1 - 3

Wet Slabs

Wet loose and slab avalanches are expected to slide naturally where the surface snow will be saturated with water.

Avoid all avalanche terrain during periods of heavy loading from new snow, wind, or rain.>

Aspects: All aspects.

Elevations: Alpine, Treeline.

Likelihood: Likely

Expected Size: 1 - 3

Deep Persistent Slabs

The rain deteriorating the late January crust could lead to avalanches stepping down to the deeper weak layers.

Be aware of the potential for very large, deep avalanches due to the presence of buried surface hoar and crust/facet layer.>

Aspects: All aspects.

Elevations: Alpine, Treeline.

Likelihood: Unlikely - Possible

Expected Size: 3 - 4