Purcells

The last storm was very reactive, and now the new storm is adding to the load above the same weak layer. I suggest conservative goals and a day of watching what happens from safe lines.

Some explosives control resulted in small avalanches from large triggers. Otherwise no new avalanches reported.

Fair - Forecast snowfall amounts are uncertain on Sunday

Overnight and Sunday: Snow fall is expected to continue into the night and then taper off by late morning. Expect 10-20 cms total at treeline with moderate West winds and strong gusts during the snow fall. A weak ridge of high pressure is expected to fill in behind the trough, shifting the winds to moderate Northerly with strong gusts.Monday: The weak ridge is expected to flatten out and let the next trough move inland from the coast. Expect mainly cloudy skies and light precipitation with light Westerly winds and the freezing level rising up to about 1000 metres.Tuesday: The next weak trough is expected to bring another pulse of precipitation to the region, combined with light West winds and slightly cooler temperatures.

New snow is adding to the recent storm slab that is between 15-30 cms across the region. This new load is expected to create another cycle of wind slab releases in the alpine and treeline, and may cause the recent storm slab to become more reactive where it is sitting on the weak surface hoar layer that was buried on February 12th. The recent storm slab has also been reactive on Southerly aspects where a sun crust formed during the period from February 8th-11th. Loading on the recent storm may cause another cycle of natural activity, or an increased sensitivity to human triggers. There are older weak layers that are now buried down around 70-80 cms and also at about 110 cms. These layers have been unlikely to trigger by skiers, but they may still be sensitive to large loads like avalanches in motion or cornice fall.