Archived

Avalanche Forecast

Apr 16th, 2018–Apr 17th, 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

2: Moderate

The avalanche danger rating at treeline will be moderate

Below Treeline

2: Moderate

The avalanche danger rating below treeline will be moderate

Regions: Glacier.

Watch for reactive surface layers. Plan your day around being finished before daytime warming increases the avalanche danger.

Weather Forecast

Snow mixed with rain at lower elevations as daytime warming pushes freezing levels up. Alpine temperatures should stay just below freezing and winds in the light range with occasional gusts to moderate. Tonight another pulse of storm should bring an additional 15cm. Snowfall should slow to flurries on Tuesday.

Snowpack Summary

Yesterday's field trip found moist storm snow up to our high point at 2100m. Ski cuts on steep rolls produced sluggish, heavy surface slab with little propagation propensity. Below 1400m the surface layer was rain soaked. The sun rapidly effected surface layers yesterday afternoon. Overnight storm snow will be insulating underlying moist snow.

Avalanche Summary

Solar input and daytime warming yesterday afternoon initiated a widespread loose wet snow avalanche cycle to size 2.5 up into the alpine on solar aspects and all aspects below treeline. These were mainly loose point release slides with the occasional thin slab release confined to the recent storm snow. Glide cracks are releasing, avoid exposure.

Confidence

Timing, track, or intensity of incoming weather system is uncertain

Avalanche Problems

Loose Wet

Loose wet slides can be expected as daytime warming pushes freezing levels upwards of 1800m. Expect surface snow layers to be moist and reactive on convexities and unsupported features treeline and below this afternoon.

Daytime warming will weaken surface layers, plan your day around being back to the trailhead early.

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

Elevations: Alpine, Treeline.

Likelihood: Likely

Expected Size: 1 - 2.5

Storm Slabs

Over 30cm in last 72hrs initially accompanied by strong to extreme S'ly winds has created storm slabs on all aspects at and above Treeline . Wind effect may have hardened the slab on alpine lee slopes. Today's snow may mask this problem.

Use caution in lee areas in the alpine and treeline. Storm snow is forming slabs.

Aspects: All aspects.

Elevations: Alpine, Treeline.

Likelihood: Possible

Expected Size: 1 - 3