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Avalanche Forecast

Feb 26th, 2018–Feb 27th, 2018
Alpine
2: Moderate
The avalanche danger rating in the alpine will be moderate
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
Alpine
2: Moderate
The avalanche danger rating in the alpine will be moderate
Treeline
2: Moderate
The avalanche danger rating at treeline will be moderate
Below Treeline
1: Low
The avalanche danger rating below treeline will be low
Alpine
2: Moderate
The avalanche danger rating in the alpine will be moderate
Treeline
2: Moderate
The avalanche danger rating at treeline will be moderate
Below Treeline
1: Low
The avalanche danger rating below treeline will be low

Regions: Purcells.

The avalanche danger may be higher on the west / southwest side of the region where recent storm totals have been greater.

Confidence

Moderate - Wind effect is extremely variable

Weather Forecast

Tuesday:3-6cm of new snow / Extreme westerly winds / Alpine temperature of -15Wednesday: Light flurries / Moderate to strong southwest winds / Alpine temperature of -8Thursday: Light flurries / Light southerly winds / Alpine temperature of -5

Avalanche Summary

In general, recent avalanche activity has consisted of mainly wind slabs (skier triggered and skier remote) in the size 1-1.5 range. However, a great Mountain Conditions Report from the peaks west of Invermere (where more snow has likely fallen) suggests conditions may be a bit spicer in that area. Click here for more details.Although deeper, persistent avalanche activity has become less frequent over the past week, light triggers in shallow rocky areas, as well as large triggers such as a cornice collapse or step down from a wind slab release still have the potential to result in large destructive avalanches.

Snowpack Summary

In the last couple of days between 5 and 30 centimetres of snow fell with the greatest accumulations occurring in the southwestern corner of the region. Winds have redistributed these accumulations into deeper, reactive slabs in wind-exposed terrain. Up to 60cm below the surface you may find an interface that was buried mid-February consisting of older wind slabs in exposed higher elevation terrain, a sun crust on steep solar aspects, and surface hoar on sheltered slopes. Several avalanches have failed on this layer in the past week.There are several persistent weak layers that are slowly beginning to show signs of improving but still remain suspect as low probability - high consequence avalanche problems. Two surface hoar layers buried in January are now 80-120 cm below the snow surface. Deeper in the snowpack (about 150 deep) is a facet/crust/surface hoar layer buried in December. Near the base of the snowpack is a crust/facet combo layer buried in late November. These layers may "wake-up" with strong inputs such as solar radiation, rapid loading/warming, or a cornice fall. Human triggering is also possible in shallow, rocky terrain.

Avalanche Problems

Wind Slabs

Light amounts of new snow and ongoing strong winds will create wind slabs in many areas in the alpine, as well as open areas at lower elevations. These slabs may be especially deep and touchy in wind-loaded areas on the leeward side of ridges.
Stay off recent wind loaded areas until the slope has had a chance to stabilize.Be cautious as you transition into wind affected terrain.

Aspects: All aspects.

Elevations: All elevations.

Likelihood: Possible - Likely

Expected Size: 1 - 2