Archived

Avalanche Forecast

Feb 5th, 2016–Feb 6th, 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

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

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

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: South Rockies.

New snow and wind have created fresh wind slabs that are ripe for human triggering.

Confidence

Moderate - Wind effect is extremely variable

Weather Forecast

Expecting 5-15cm of snow by Saturday Morning and then drying out for remainder of period. Friday's snow will be accompanied by strong southwesterly winds. Winds remain moderate westerly on Saturday morning before easing off for the remainder of the period. Freezing levels remain at valley bottom until they rise sharply to near 2000m on Monday.

Avalanche Summary

A size 2 cornice triggered persistent slab which likely failed on a surface hoar layer buried in early January was observed on Thursday.

Snowpack Summary

5cm of new snow overnight with strong gusty winds in variable directions have created fresh 20-30cm wind slabs in areas you might not normally expect to find them such as aspects that are generally windward and well below ridge tops. A persistent weak layer of buried surface hoar can be found at variable depths depending on elevation. A weak crust/facet layer from early-December can typically be found down over 1m. Below 1700m the most recent snow hides a melt-freeze crust.

Avalanche Problems

Wind Slabs

New snow and variable strong winds have created touchy wind slabs in areas you may not expect them.

Avoid freshly wind loaded features.>Be cautious as you transition into wind affected terrain.>Use ridges or ribs to avoid pockets of wind loaded snow. >

Aspects: All aspects.

Elevations: Alpine, Treeline.

Likelihood: Possible - Likely

Expected Size: 1 - 3

Persistent Slabs

Be aware of the potential for large, deep avalanches due to the presence of buried surface hoar.>

Aspects: All aspects.

Elevations: All elevations.

Likelihood: Unlikely - Possible

Expected Size: 3 - 5