Avalanche Forecast

Issued: Mar 31st, 2013 9:28AM

The alpine rating is moderate, the treeline rating is low, and the below treeline rating is low. Known problems include Cornices and Loose Wet.

mpeter, Avalanche Canada

South Columbia.

Danger could INCREASE TO CONSIDERABLE with intense radiation on south and west aspects, especially at treeline and below. Be aware of how the warm weather is changing the snowpack.

Summary

Confidence

Good

Weather Forecast

Monday: One more warm day! Expect clear, sunny skies, light northwesterly winds and alpine temperatures to reach 2 with freezing levels at 2600.Tuesday/Wednesday: The ridge should begin to break down. Light/thin clouds are possible with temperatures slowly falling to more seasonal values. Expect light to moderate westerly winds. There is a slight chance of isolated flurries developing late on Wednesday.

Avalanche Summary

Solar aspects have been very active showing loads of natural loose wet avalanches and cornice releases up to size 2.5.

Snowpack Summary

Surface faceting and surface hoar growth ( up to 20 mm) has been prevalent on shady slopes at upper elevations, while the surface snow on sun-exposed slopes and at lower elevations has been subject to daily melt-freeze cycles. Cornices are large and weak.Surface hoar buried March 10th is down 100cm in most places. This layer seems to be bonding in most places and is a low probability - high consequence problem. Triggering may be possible with a very large load (cornice fall) or hitting the sweet spot in thin, variable snowpack areas.

Problems

Cornices

Cornice falls are a concern during warming. Slopes with corniced entrances, or exposed to cornice falls should be avoided. It is possible that the weight of a cornice dropping onto the slope below could trigger an avalanche on the Mid-March crust.

Stay well back from cornices.>Be wary on slopes that are exposed to cornices overhead.>

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

Elevations: Alpine.

Likelihood

Likely

Expected Size

2 - 6

Loose Wet

Warm temperatures and strong solar radiation may cause loose moist or wet snow avalanches. Keep an eye on changing conditions: Avalanche activity, snowballing, moist and wet snow are initial indicators of deterioration and increased hazard.

Avoid sun exposed slopes when the solar radiation is strong, especially if snow is moist or wet.>Watch for wet slab activity with forecast warm temperatures.>

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

Elevations: All elevations.

Likelihood

Very Likely

Expected Size

1 - 4

Valid until: Apr 1st, 2013 2:00PM