Quartz creek- Rolly Polly

Skiing short pitches at 2100m TL today we observed widespread touchy storm slabs down 30-50cm that were reactive to skier traffic. We ski cut and accidentally triggered several Sz 1 avalanches and Ski cut one Sz. 1.5 off of steep unsupported roll. All seem to be failing on Jan 31 interfaceor old Windslab. Got surprised by the propagation of the soft (F to 4F) storm slab. Lots of audibles coming from the alpine in the pm (No visibility).