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Avalanche Forecast

Dec 9th, 2016–Dec 10th, 2016
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
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

Regions: Northwest Inland.

Wind is the major weather factor to keep a close eye on this weekend. Wind slabs may be encountered on unexpected aspects due to strong outflow winds.

Confidence

Moderate - Wind speed and direction is uncertain

Weather Forecast

Saturday: Mostly sunny / Light to moderate easterly winds / High of -19 C.Sunday: Sunny / Light to moderate easterly winds / High of -19 C. Monday: Sunny / Light to moderate northeasterly winds / High of -18 C.

Avalanche Summary

Wind slabs are a concern in open areas at treeline and above. No new avalanches were reported on Thursday; however, check out the recent MIN report for the Miller Creek/ Crater Lake area. That report indicated a natural size 2 slab avalanche which appeared to be a cornice failure in steep complex terrain. The avalanche was noted from a southeast aspect at 1850 m.

Snowpack Summary

Clear skies and strong outflow winds have created a variety of snow surfaces including scouring and hard wind slabs in exposed areas and surface hoar formation in sheltered areas. Recent winds have blown from many directions, most recently from the east. As a result, expect wind slabs to exist on a wide variety of exposed slopes. A layer of surface hoar was reported around Hudson Bay Mountain last week, which now sits beneath 40-50 cm of settling snow. A thick rain crust that formed in early November is now buried 50-60 cm deep, and recent snowpack tests produced sudden results on facets (sugary snow) above this crust. Early season snowpack observations are still very limited in the region, but reports suggest the average snowpack depth is 50-90 cm at treeline and 120 cm or greater in the alpine.

Avalanche Problems

Wind Slabs

New wind slabs may exist in the alpine and on exposed features at treeline. Wind slabs may be touchy in areas with buried surface hoar.
Tread cautiously on open slopes and convex rolls where buried surface hoar may be preserved.Watch your transition into wind affected terrain. Some areas may have been reverse loaded by winds.

Aspects: All aspects.

Elevations: Alpine, Treeline.

Likelihood: Possible

Expected Size: 1 - 2