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Avalanche Forecast

Mar 6th, 2014–Mar 7th, 2014
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
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
3: Considerable
The avalanche danger rating below treeline will be considerable
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

Regions: Northwest Inland.

We should see conditions start changing on Friday but I'm anticipating slow build. Avalanche danger could jump to considerable on Friday if the weather arrives early or with greater intensity than forecast.

Confidence

Fair

Weather Forecast

Friday: Snow picking up throughout the day – 10-15 cm. The freezing level climbs to 1500 m in the south and 500 m in the north. Winds are crankin’ from the S-SW. Saturday: Cloudy with periods of snow and possible sunny breaks. The freezing level is between 1000 in the north and 1500 m in the south. Winds are strong from the S-SW. Sunday: Cloudy with flurries. The freezing level is around 1400 m lowering throughout the day. Winds are moderate to strong from the S-SW.

Avalanche Summary

No new avalanche activity reported. This could change on Friday with forecast snowfall, warming and strong winds.

Snowpack Summary

Persistent cold dry weather has resulted in significant new surface hoar growth and surface facetting on shady slopes at all elevations. Steep solar aspects may have a sun crust. The early February weak layer of facets, crusts, and surface hoar is buried down about 35-80 cm. The snow above the crust has been transported by Southwest winds and then reverse loaded by Easterly or Southeast winds. Cold temperatures have not settled the snow above the weak layer into a cohesive slab, and the cold has preserved the weak layer and associated crusts. Basal facets and depth hoar remain a concern in areas with thin or variable snow cover.

Avalanche Problems

Persistent Slabs

New loading from snow and wind, combined with significant warming, could "wake up" the mid  February persistent weak layer and create large avalanches. 
Use conservative route selection, stick to moderate angled terrain with low consequence.>Avoid open slopes and convex rolls at and below treeline where buried surface hoar may be preserved.>

Aspects: All aspects.

Elevations: All elevations.

Likelihood: Possible

Expected Size: 2 - 5

Wind Slabs

New dense wind slabs should build throughout the day. Triggering will be most likely in steep, exposed lee terrain at and above treeline. 
Be cautious as you transition into wind affected terrain.>Choose well supported terrain without convexities.>

Aspects: All aspects.

Elevations: Alpine, Treeline.

Likelihood: Possible - Likely

Expected Size: 1 - 3