Archived

Avalanche Forecast

Dec 8th, 2016–Dec 9th, 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

1: Low

The avalanche danger rating at treeline will be low

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

1: Low

The avalanche danger rating at treeline will be low

Below Treeline

1: Low

The avalanche danger rating below treeline will be low

Regions: Northwest Inland.

Be on the lookout for pockets of wind slab below alpine ridges. Sunny skies can make these slabs increasingly sensitive, even on cold days.

Confidence

Moderate - Due to the number of field observations

Weather Forecast

Friday: Mostly sunny / Strong to moderate easterly winds diminishing in the afternoon / Weak inversion with a alpine high of -16 C.Saturday: Mix of Sun and cloud / Light to moderate easterly winds / Alpine high of -18 C.Sunday: Sunny / Light easterly winds / Alpine high of -16 C.

Avalanche Summary

Wind slabs avalanches are a concern where wind is being blown around. No new avalanche reports on Wednesday; however, check out the recent MIN report for the Miller Ck/ Crater Lk 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

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.

Watch your transition into wind affected terrain. Some areas may have been reverse loaded by winds.Tread cautiously on open slopes and convex rolls where buried surface hoar may be preserved.

Aspects: All aspects.

Elevations: Alpine, Treeline.

Likelihood: Possible

Expected Size: 1 - 2