Archived

Avalanche Forecast

Mar 12th, 2018–Mar 13th, 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

3: Considerable

The avalanche danger rating below treeline will be considerable

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

3: Considerable

The avalanche danger rating below treeline will be considerable

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

3: Considerable

The avalanche danger rating below treeline will be considerable

Regions: Glacier.

Spring has arrived! Daytime warming and strong solar radiation will destabilize surface layers as the day progresses. Loose wet avalanches are certain on steep solar aspects.

Weather Forecast

A mix of sun and cloud for today with freezing levels up to 2100m and light southerly winds. Tuesday through Wednesday freezing levels are forecast to rise up to 2700m with an alpine high up to 4C.

Snowpack Summary

The snowpack is beginning to transition to a spring snowpack. Two days of strong sun has heated the surface and created a crust on solar aspects. Above freezing temps at valley bottom have created a surface crust below ~1500m. The recent storm snow with strong S'ly winds created pockets of windslab in the alpine. Deep PWLs are buried over 1.5m.

Avalanche Summary

Solar aspects are shedding their surface layers of snow throughout the forecast area. Several avalanches to size 3 from steep solar aspects in the highway corridor. These slides started as early as noon yesterday.

Confidence

The weather pattern is stable

Avalanche Problems

Loose Wet

Expect loose wet avalanches to initiate from steep solar terrain. Pay close attention to the effects of the sun on the avalanche terrain above you and avoid overhead exposure. With prolonged warm temps expect cornices to begin failing.

Avoid exposure to overhead solar avalanche terrain, avalanches may reach the end of run out zones.

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

Elevations: All elevations.

Likelihood: Likely

Expected Size: 1 - 3

Wind Slabs

Strong south winds and recent storm snow have created isolated wind slabs. Expect to find pockets of windslab in the immediate lee of ridges and crossloaded features in the alpine.

Be careful with wind loaded pockets, especially near ridge crests and roll-overs.Use caution in lee areas. Recent wind loading has created wind slabs.

Aspects: All aspects.

Elevations: Alpine.

Likelihood: Possible

Expected Size: 1 - 2

Persistent Slabs

Sun crusts are buried 30-60 cm on steep solar aspects. This interface provides a smooth bed surface and may contribute to larger than expected avalanches. It is possible for smaller avalanches to trigger this lingering problem.

Minimize exposure to steep, sun exposed slopes when the solar radiation is strong.

Aspects: North, North East, East.

Elevations: Alpine, Treeline.

Likelihood: Unlikely - Possible

Expected Size: 2 - 3