Archived

Avalanche Forecast

Mar 5th, 2013–Mar 6th, 2013

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

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

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: Cariboos.

Confidence

Fair - Timing or intensity of solar radiation is uncertain on Wednesday

Weather Forecast

Overnight and Wednesday: Cool, sunny and dry with light Southeast winds. Freezing level rising to about 700 metres during the day.Thursday:Continued cool and dry with overnight lows down to about -6.0 and daytime freezing levels rising to about 1000 metres. Light Southwest winds are expected during the day.Friday:More dry sunny weather is expected.

Avalanche Summary

We continue to get reports of natural avalanches up to size 3.0 that happened during the storm, or after the storm on solar aspects in the alpine.

Snowpack Summary

New sun crusts are reported to be forming on solar exposed aspects as the spring sun starts to pack more of a punch. The recent storm snow is settling, but storm slab releases are still possible. The weak layer of surface hoar that was buried around February 12th may be triggered by storm snow avalanches in motion, or by cornice fall and other large triggers. The strong solar radiation may trigger some cornice fall or release moist point releases in steep terrain that may step down to one of the deeper weak layers. I expect that the next couple of days will be a tricky combination of avoiding areas that slid during the warm wet weather, and gaining confidence in the areas that did not slide.

Avalanche Problems

Storm Slabs

The recent storm snow continues to settle and bond, but may continue to be triggered by human activity. Strong solar radiation may cause increased activity on sun exposed aspects.

The new snow will require several days to settle and stabilize.>

Aspects: All aspects.

Elevations: Alpine, Treeline.

Likelihood: Possible

Expected Size: 3 - 6

Cornices

Recent cornice growth may not be well bonded and may fall off naturally during periods of strong solar radiation.

Extra caution needed around cornices with current conditions.>Stay well back from cornices.>

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

Elevations: Alpine, Treeline.

Likelihood: Possible - Likely

Expected Size: 1 - 4

Persistent Slabs

There is a weak layer of surface hoar buried down about 100-150 cms (February 12th layer) that may continue to be triggered by large forces like cornice fall or storm snow avalanches in motion.

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

Aspects: All aspects.

Elevations: Alpine, Treeline.

Likelihood: Possible

Expected Size: 4 - 7