Archived

Avalanche Forecast

Feb 19th, 2014–Feb 20th, 2014

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

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

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.

Stick to simple, well-supported terrain with little overhead hazard. Let the snowpack heal itself before you launch into powder-seeking mode.

Weather Forecast

Mainly cloudy today with isolated flurries and gusting moderate to strong westerly winds. Freezing levels will remain in the valley bottoms. Thursday will bring more flurries, amounting to 5-10cm, along with moderate to strong westerly winds and cool temp's. A drying trend will begin on Friday.

Snowpack Summary

100-140cm of recent storm snow, deeper amounts west side of the summit, is settling over the Feb 10 facet/surface hoar/crust interface. The Jan 28Â and Jan 22 surface hoar layers are 5-10cm below this interface. Test results yesterday above Hermit Hut had sudden planar results on the Feb 10 interface, including one large "whumph" at the test site.

Avalanche Summary

Avalanche control overnight produced numerous size 2-3.5's from all aspects, with many slides extending into the end of the run-out zone. The strong S-SW winds overnight likely produced natural activity in open alpine and tree-line elevations.

Confidence

Avalanche Problems

Storm Slabs

As the slab over the weak layers down 100-140cm becomes more cohesive, it changes in how it reacts to a riders weight. The highly reactive stage may have passed, but it is at a depth where triggering is less frequent but much more dangerous.

Remote triggering is a concern, watch out for adjacent slopes.Choose well supported terrain without convexities.

Aspects: All aspects.

Elevations: All elevations.

Likelihood: Possible - Likely

Expected Size: 2 - 3

Wind Slabs

Strong winds overnight from the S-SW will have created surface wind slabs in the alpine and tree-line.

Avoid freshly wind loaded features.Be cautious as you transition into wind affected terrain.

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

Elevations: Alpine, Treeline.

Likelihood: Possible - Likely

Expected Size: 1 - 3

Cornices

The cornices have undergone tremendous growth in the past week with all the new snow and winds. These cornices could be the large load to trigger the thick slabs overlying the Feb 10th interface. Expect large avalanches if caused by cornice-fall!

Give cornices a wide berth when travelling on or below ridges.Pay attention to overhead hazards like cornices.

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

Elevations: Alpine.

Likelihood: Possible

Expected Size: 2 - 4