Archived

Avalanche Forecast

Mar 14th, 2017–Mar 15th, 2017

Alpine

4: High

The avalanche danger rating in the alpine will be high

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

4: High

The avalanche danger rating in the alpine will be high

Treeline

4: High

The avalanche danger rating at treeline will be high

Below Treeline

4: High

The avalanche danger rating below treeline will be high

Alpine

4: High

The avalanche danger rating in the alpine will be high

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.

Elevated freezing levels, rapid snow settlement and touchy storm slab formation are leading to increased human triggered and natural avalanche hazard.

Weather Forecast

A band of warm moist air will bring elevated freezing levels (1900m+) and precipitation in the form of both snow and rain to the forecast area today with forecast amounts in the 10cm range. Cooling temps, and upwards of 30cm of snowfall are expected tonight through Wednesday accompanied by moderate SW winds. Look for an increasing avalanche danger.

Snowpack Summary

80cm+/- of new snow since Saturday. Warming temperatures have made for moist surface snow up to 2100m.This will be making for rapid settlement and storm slab formation through all elevation bands. Moderate S'ly winds have formed windslab on alpine lee slopes On solar aspects the late Feb crusts are down 70-120cm in the snowpack.

Avalanche Summary

Numerous natural avalanches occurred in the highway corridor in the last 48hrs. These slides were size 2-3 with several running full path. Avalanche control on Sunday gave numerous large avalanches running to full path. Expect that a widespread natural avalanche cycle has occurred in the back country as well. Freezing levels remain high

Confidence

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

Avalanche Problems

Storm Slabs

80cm of recent snowfall and warming temps yesterday and today are forming a reactive storm slab. Numerous full path avalanches have occurred in the last 48hrs.

If triggered the storm/wind slabs may step down to deeper layers resulting in large avalanches.Avoid exposure to overhead avalanche terrain, large avalanches may reach the end of run out zones.

Aspects: All aspects.

Elevations: All elevations.

Likelihood: Likely - Very Likely

Expected Size: 1 - 3

Persistent Slabs

Buried crusts on solar aspects are hidden under our recent storm snow. Skiers were able to trigger slab avalanches on this layer earlier in the week. Avalanches triggered in the storm snow have a high probability to overload this layer.

Avoid unsupported features.Be aware of the potential for wide propagations.

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

Elevations: All elevations.

Likelihood: Possible - Likely

Expected Size: 1 - 4