Avalanche Forecast

Issued: Jan 3rd, 2017 5:20PM

The alpine rating is moderate, the treeline rating is moderate, and the below treeline rating is low. Known problems include Wind Slabs and Persistent Slabs.

Avalanche Canada shorton, Avalanche Canada

South-facing slopes and areas with thin snowpacks are the most suspect for avalanche activity.

Summary

Confidence

Moderate - Due to the number of field observations

Weather Forecast

WEDNESDAY: Cloudy, 20-30 km/h north winds, alpine temperatures around -18.THURSDAY: Cloudy with isolated flurries and trace accumulations, light west winds, alpine temperatures around -16.FRIDAY: Cloudy with isolated flurries, light southwest winds, alpine temperatures around -14.

Avalanche Summary

Reports from the region are limited to old size 2 wind slabs that occurred during the major wind event on New Years Day. The reports suggest wind loading occurred in open terrain at all elevations and aspects. Lingering wind slabs may remain reactive to human triggering on specific features, such as the immediately lee of ridges and sun-exposed slopes.

Snowpack Summary

Strong winds on Sunday had an extensive effect in exposed terrain at all elevations. Expect scouring, hard wind slabs, and thicker reactive wind slabs in unusual places as the winds shifted from west to northeast. Sunny weather is likely making the wind slabs extra touchy on south-facing slopes. The mid-December facet/surface hoar interface can be found buried 50-100 cm deep. The interface has been showing signs of gaining strength in thick snowpack areas, but remains a concern in thin snowpack areas throughout the region. The lower snowpack is well bonded and features a thick rain crust near the ground.

Problems

Wind Slabs

An icon showing Wind Slabs
Southerly aspects are wind loaded and becoming unstable with solar warming. Watch for wind slabs in unusual places, including open areas at lower elevations.
Be cautious as you transition into wind affected terrain.Avoid travelling in areas that have been reverse loaded by winds.Minimize exposure to sun exposed slopes when the solar radiation is strong.

Aspects: All aspects.

Elevations: Alpine, Treeline.

Likelihood

Possible

Expected Size

1 - 3

Persistent Slabs

An icon showing Persistent Slabs
Triggering a weak layer of facets may still be possible in parts of the region with thin snowpacks. Dig down and test for weak layers before committing to any steep slope.
Minimize exposure to steep, planar south facing alpine slopes.Choose regroup spots that are out of avalanche terrain.Avoid convexities or areas with a thin or variable snowpack.

Aspects: All aspects.

Elevations: All elevations.

Likelihood

Unlikely

Expected Size

2 - 3

Valid until: Jan 4th, 2017 2:00PM