While Transtioning to ride the south face /two trees on superior ridgline we encountered high winds and large cornices developed from last night/this morning overhanging the North side with lots of windloading. We were careful, but unintentionally trigged a small cornice break that ended up propogating a decent avalanche on what I would call Power outage face. It moved quick and ran the whole slope. No parties were below or near the avalanche path. The slide was at 10200 feet and North facing. The slab propogation was consistently 2ft deep maybe a little more in some areas, failing on a faceted bed surface.