Avalanche Forecast

Issued: Feb 9th, 2018 4:22PM

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

Avalanche Canada swerner, Avalanche Canada

A spike in natural avalanche activity may occur due to strong solar effect.

Summary

Confidence

Moderate -

Weather Forecast

The weather pattern has taken a dramatic shift as the arctic ridge becomes the dominant weather feature through the weekend, bringing colder temperatures and mostly clear skies.Saturday: Sunny with alpine temperatures near -3 and freezing levels 1400 m. Ridgetop winds light from the West. Sunday: A mix of sun and cloud with some flurries. Alpine temperatures near -7 and freezing levels 1000 m. Ridgetop winds light from the northwest.Monday: A mix of sun and cloud. Alpine temperatures near -3 and freezing levels 1100 m. Possible alpine inversion. Ridgetop winds light from the northeast.

Avalanche Summary

On Friday, no new avalanches were reported.On Thursday, avalanche control with explosives triggered numerous slab avalanches up to size 2. Cornice releases triggered wind slabs from the slopes below up to size 1.5. With colder temperatures expected this weekend, natural avalanche activity will likely taper off, but human triggering will be possible especially on leeward slopes and behind terrain features.

Snowpack Summary

Snow surfaces vary from aspect to elevation showing crusts, wind pressed and scoured conditions. In the alpine 5-15 cm of recent snow, accompanied by strong winds from the southeast have formed reactive wind slabs up to 30 cm thick in leeward terrain. Large, fragile cornices exist on ridgelines and could trigger an avalanche on the slope below if they fail. Treeline and below treeline elevations a melt-freeze crust has formed.On average 180 cm of settled snow now sits on the mid-January crust which generally shows signs of bonding to the overlying snow; however, it has the potential to "wake-up" with a large trigger such as a cornice fall. Below this, the snowpack is thought to be generally strong and well-settled.

Problems

Wind Slabs

An icon showing Wind Slabs
Wind slabs remain reactive to rider triggers, especially on leeward slopes and behind terrain features.
Watch for signs of instability such as whumpfing, or cracking. Be cautious as you transition into wind affected terrain.

Aspects: North, North East, East, South East, South.

Elevations: Alpine, Treeline.

Likelihood

Possible - Likely

Expected Size

1 - 2.5

Cornices

An icon showing Cornices
Large looming cornices exist along ridgelines. They require respect and discipline. Give them an extra wide berth from above and below.
Give cornices a wide berth when travelling on or below ridges.Falling cornices may trigger large avalanches on the slopes below.

Aspects: North, North East, East, South East.

Elevations: Alpine, Treeline.

Likelihood

Possible

Expected Size

1.5 - 2.5

Valid until: Feb 10th, 2018 2:00PM