Avalanche Forecast

Issued: Jan 9th, 2021 4:00PM

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

snow safety,

Email

Conditions are improving, but there are a number of weak layers in the snowpack that still make triggering larger avalanches possible at treeline and above.

Summary

Weather Forecast

Expect winds to increase to the strong range through out Sunday with cloudy conditions.

Moving into Monday winds will be similar, in the strong range with consistent cloud cover.

Snowpack Summary

Recent storm snow totals are 20-50 cm at treeline. This sits on a spotty stellar/surface hoar layer in some locations. Wind effect in open areas in the alpine. Two weak layers from early Dec persist 50-100 cm down. These have been generally unreactive but still giving hard sudden planar results. The Nov. 5 basal crust/facets are currently dormant.

Avalanche Summary

No new activity today besides some sz 1 explosive triggered thin wind slabs in the alpine at the ski hills. One notable, size 2 skier remote on Mt. Hector South at treeline two days ago; this was likely on one of the mid December persistent layers. This shows that it is still possible to trigger in the right (or wrong) location.

Confidence

Timing of incoming weather systems is uncertain on Tuesday

Problems

Persistent Slabs

An icon showing Persistent Slabs

A spotty layer of stellars and surface hoar 25-50 cm down is most likely an issue in steep treeline terrain, but is present in some alpine locations. Two other layers from Dec persist and still produce hard sudden planar results.

  • Dig down to find and test weak layers before committing to a piece of terrain.
  • Convex features and steep unsupported slopes will be most prone to triggering.

Aspects: All aspects.

Elevations: Alpine, Treeline.

Likelihood

Possible

Expected Size

1 - 2

Wind Slabs

An icon showing Wind Slabs

Previous winds have created slabs, however recent observations have only found them in specific alpine areas, and haven't been very reactive. Watch locally on your trip for slab formation. Some of these slabs will be buried under new snow.

Aspects: All aspects.

Elevations: Alpine.

Likelihood

Unlikely - Possible

Expected Size

1 - 2

Valid until: Jan 10th, 2021 4:00PM