Archived

Avalanche Forecast

Jan 8th, 2018–Jan 9th, 2018

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

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

4: High

The avalanche danger rating in the alpine will be high

Treeline

4: High

The avalanche danger rating at treeline will be high

Below Treeline

3: Considerable

The avalanche danger rating below treeline will be considerable

Regions: South Coast.

25 to 30 cm of warm snow is expected Monday night. Human triggered avalanches are likely Tuesday, especially in steep wind-loaded terrain above treeline. Choose conservative lines and watch for clues of instability.

Confidence

Moderate - Timing, track, or intensity of incoming weather system is uncertain

Weather Forecast

Continued precipitation is expected through Monday night before a brief lull in the action Tuesday and Wednesday. Thursday's system looks pretty juicy, stay tuned for details. MONDAY NIGHT: Overcast, freezing level around 1200 m, snowline around 1000 m, moderate southwest wind, 25 to 30 cm of snow.TUESDAY: Overcast, freezing level around 1000 m lowering through the day, moderate west wind, no snow expected.WEDNESDAY: Overcast, freezing level around 800 m, light scattered wind, up to 5 cm of snow possible. Up to 30 cm possible Wednesday night.THURSDAY: Overcast, freezing level may rise as high as 1200 m, strong west wind, 15 to 30 cm of snow possible.

Avalanche Summary

On Monday storm slabs were sensitive to skier triggering to size 1.0 on northwest through southeast facing features with crowns 10 to 15 cm in depth.

Snowpack Summary

As of Monday afternoon, 20 to 40 cm of rain soaked snow had fallen on the January 7th crust. Looking down into the snowpack there are a few prominent melt-freeze crusts that were buried mid-December and are now 50 to 100 cm below the surface. After heavy rain last Friday penetrated most of the snowpack, these crust layers have been reported to be bonding to the snow above and below. The rain last week has reduced the snowpack depth at 1000 m to about 140 cm and many early season hazards are still present.

Avalanche Problems

Storm Slabs

Another 25 to 30 cm of warm snow Monday night is expected to add to the 20 to 40 cm of rain soaked storm snow that has fallen over the last few days. This snow may react as a storm slab in steep terrain or as a wind slab in wind exposed features.

Be careful with wind loaded pockets, especially near ridge crests and roll-overs.Watch for signs of instability such as whumpfing, or cracking. Use caution in lee areas in the alpine and treeline. Recent storm snow has formed slabs.

Aspects: All aspects.

Elevations: Alpine, Treeline.

Likelihood: Likely

Expected Size: 1 - 2

Loose Wet

Loose wet avalanches may still be problematic Tuesday morning in steep terrain where precipitation has fallen as rain.

Avoid exposure to terrain traps where the consequences of a small avalanche could be serious.

Aspects: All aspects.

Elevations: Alpine, Treeline.

Likelihood: Possible - Likely

Expected Size: 1 - 2