Archived

Avalanche Forecast

Feb 17th, 2016–Feb 18th, 2016

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.

Warm temp's today/tomorrow will keep the storm slab touchy. Cornices looming overhead should also be of concern.

Weather Forecast

Cool morning temp's but a rapid warming by noon will see freezing levels rise to 1800m. Otherwise, today will be mainly cloudy with isolated flurries, and light ridge-top winds. A minor front rolls through Wed night, bringing 10-15cm, mod SW winds, and elevated freezing levels around 1700-1800m through much of Thursday.

Snowpack Summary

Rogers Pass received 85cm of snow in the past week. Slab development has been widespread in the area, with mild temp's and strong S-SW winds creating a reactive layer. On solar aspects this slab sits on a crust. The mild temp's will promote bonding of the slab to the underlying surfaces, but this takes time. Below 1600m, expect heavy, moist snow.

Avalanche Summary

The natural avalanche cycle seems to have slowed down. No reports of human-triggered avalanches yesterday. However, 3 from Monday and a serious one involving an injured skier on Sunday underline the fact that the storm slab needs time to bond. Artillery control yesterday produced many slides to size 2.5-3, with a few larger 3.5's.

Confidence

Due to the number of field observations

Avalanche Problems

Storm Slabs

The storm slab will be a little more touchy once temp's warm up later in the day. It isn't the time to charge into aggressive terrain.

The new snow will require several days to settle and stabilize.Use conservative route selection, choose moderate angled and supported terrain with low consequence.

Aspects: All aspects.

Elevations: All elevations.

Likelihood: Possible - Likely

Expected Size: 2 - 3

Wind Slabs

Consistently moderate to strong winds have created windslabs in alpine and tree-line areas.

Be cautious as you transition into wind affected terrain.Existing tracks in the snow are a poor guide to good route selection.

Aspects: All aspects.

Elevations: Alpine, Treeline.

Likelihood: Possible - Likely

Expected Size: 2 - 3