Avalanche Forecast

Issued: Dec 26th, 2019 3:00PM

The alpine rating is moderate, the treeline rating is moderate, and the below treeline rating is moderate. Known problems include Storm Slabs.

Avalanche Canada cgarritty, Avalanche Canada

Forecast new snow is not expected to bond well to the current surface. Wind-loaded areas will likely hold deeper, more reactive new slabs on Friday.

Summary

Confidence

Moderate - Forecast snowfall amounts are uncertain.

Weather Forecast

Thursday night: Cloudy with flurries bringing 15-20 cm of new snow by morning. Moderate to strong south winds.

Friday: Mainly cloudy. Light to moderate northwest winds. Alpine high temperatures around -4 with freezing levels to 1000 metres.

Saturday: Cloudy with scattered flurries bringing 5-10 cm of new snow, transitioning to wet flurries overnight. Moderate to strong south winds. Alpine high temperatures around -1 with freezing levels to 1000 metres, rising to 1500 metres overnight.

Sunday: Cloudy with isolated wet flurries and a trace to 3 cm of new snow. Light southeast winds. Alpine high temperatures around 0 with freezing levels to 1500 metres.

Avalanche Summary

No new avalanches have been reported in the region since the widespread natural avalanche cycle brought on by the storm at the end of last week.

Looking forward, expect new snow forecast over Thursday night to form a new storm slab problem to manage on Friday. Thicker, more reactive slabs should be expected at higher, more wind-exposed elevations.

Snowpack Summary

A new melt-freeze crust has been observed on the surface of sun-exposed aspects. Below it, 50-100 cm of snow from the storm at the end of last week forms the region's upper snowpack above about 1200 metres.

Collectively, this storm snow is well settled and has formed strong bond with the melt-freeze crust present on the previous surface. Below this interface the lower snowpack is well settled and strong.

Below 1200 metres, our recent snow amounts diminish rapidly with elevation and are capped by a melt-freeze crust.

Terrain and Travel

  • Carefully monitor the bond between the new snow and old surface.
  • Use small low consequence slopes to test the bond of the new snow.
  • Dial back your terrain choices if you are seeing more than 20 cm of new snow.

Problems

Storm Slabs

An icon showing Storm Slabs

15-20 cm of new snow in Thursday night's forecast will create a new storm slab problem to manage on Friday. Thicker, more reactive slabs are expected to form at wind-exposed higher elevations. Expect new snow to bond poorly with the surface over the near term.

Aspects: All aspects.

Elevations: All elevations.

Likelihood

Likely

Expected Size

1 - 2

Valid until: Dec 27th, 2019 5:00PM