Avalanche Forecast
Issued: Apr 4th, 2014 9:11AM
The alpine rating is Wind Slabs and Deep Persistent Slabs.
, the treeline rating is , and the below treeline rating is Known problems includeSummary
Confidence
Fair - Freezing levels are uncertain
Weather Forecast
Overnight and Saturday: Moderate Westerly winds overnight and freezing levels dropping down to 1500 metres. Strong Southwest winds developing in the afternoon as the freezing level rises up to 2000 metres.Sunday: Freezing levels remaining near 2000 metres. Some light precipitation overnight ending as winds shift to the Northwest.Monday: Freezing levels climb to 3000 metres as warm air moves into the region. Chance of broken skies and periods of strong solar radiation. Winds light to moderate from the Southwest.
Avalanche Summary
Some very large avalanches up to size 3.0 were reported from the Harvey pass area. These natural avalanches may have been a couple of days old, and it is suspected that they either ran on or stepped down to the February deep persistent weak layer. Avalanches releasing on this layer may become more likely during the forecast very warm weather early next week.
Snowpack Summary
Solar radiation and high freezing levels have created new melt-freeze crusts on Southerly aspects. The 20-40cm of recent new snow sits on top of a thick sun crust on solar aspects. 70-90 cm of settling storm snow from the past week rests on a graupel layer that can be found in much of the region. This makes for around 90 cm on top of the mid march crust at this point. This crust exists on all aspects below 2000m and on solar aspects in the high alpine. North of Sparwood and in the Crowsnest Pass area, the buried crust seems more specific to previously sun-exposed slopes. The deep facet/crust persistent weakness buried at the beginning of February (now down 140 to 170cm) seems unlikely to trigger in areas where the hard, supportive crust exists. No matter where you are in the region, this weakness should stay on your radar as any activity at this interface would be large and destructive. Possible triggers include a large cornice fall, a large input in a thin snowpack area or solar warming.
Problems
Wind Slabs
Aspects: North, North East, East, South East.
Elevations: Alpine, Treeline.
Likelihood
Expected Size
Deep Persistent Slabs
Aspects: All aspects.
Elevations: All elevations.
Likelihood
Expected Size
Valid until: Apr 5th, 2014 2:00PM