Backside Falcon/Big White incident

Witnessed an individual ski a very obviously windloaded north facing slope behind Falcon chair at Big White and trigger a slab that propagated. They were able to cut across far enough to beat the propagation. Approx size 1 slab ~20-30cm crown, ran ~50m propagated under skiers pressure ~ 100m. I dug a quick pit nearby in a safe location. The wind slab is wide spread across the North aspects and is ~10-20+cm thick in some areas. I found the slab had significant breaking energy under my tests.