Avalanche Forecast
Issued: Mar 17th, 2012 4:00PM
The alpine rating is Persistent Slabs, Storm Slabs and Wind Slabs.
, the treeline rating is , and the below treeline rating is Known problems includeSummary
Confidence
Fair - Timing or intensity of solar radiation is uncertain on Sunday
Weather Forecast
There are remnants of a system moving up from south of the border that may bring some moisture into the North Columbia mountains on Saturday night. Unsettled conditions are expected across the Interior regions again on Sunday. Some areas may see periods of heavy convective flurries, while others may see broken skies or scattered cloud. Winds should stay mostly light from the south, and the freezing level is expected to drop to the valley bottom Saturday night and then rise to about 800 metres on Sunday. Monday is forecast to be unsettled again, but with more likelihood of sunny periods. A Pacific frontal system is expected to start moving in from the coast on Tuesday bringing strong westerly winds and heavy precipitation.
Avalanche Summary
Avalanche activity continued on Friday with naturals reported up to size 2.5. Forecast sunshine over the next few days may cause another natural avalanche cycle.
Snowpack Summary
Periods of sunshine have caused moist snow on solar aspects up to about 1500 metres. Recent cornice growth has made cornices unstable. The new snow has added to the well consolidated storm slab that overlies weak surfaces that formed early February. This interface, which lies between 1 and 2 metres below the surface, includes a widespread surface hoar instability that, depending on aspect an elevation, may exist in combination with facets or crusts. These persistent weak layers have been reactive all week and remain a concern at all elevations. The weight of new snow, near-surface avalanches, sleds, and skiers may easily trigger these deeper weaknesses creating unexpectedly large and destructive avalanches.
Problems
Persistent Slabs
Aspects: All aspects.
Elevations: All elevations.
Likelihood
Expected Size
Storm Slabs
Aspects: All aspects.
Elevations: All elevations.
Likelihood
Expected Size
Wind Slabs
Aspects: North, North East, East, South East, South, South West.
Elevations: Alpine, Treeline.
Likelihood
Expected Size
Valid until: Mar 18th, 2012 9:00AM