The recent wet storm and barely-freezing temperatures at Tony Grove made us wary of steeper slopes today. Observed collapsing earlier in the day on a flat ridgeline E of the Bear River Divide. Did not observe any wet slides despite warmer temperatures and overcast greenhousing. Unintentionally ski triggered a slide on a N/NE facing 30-32 degree slope at ~8900'. The slide propagated below a rollover that broke 150' wide with a 1-2' deep crown and ran for 450' to the bottom of the run. The slab dropped down through two storm layers and failed on a thick layer of buried surface facets and a firm bed layer. Wet debris piled up 3-5' on the uphill side of well-spaced trees. Observed recent snowmobile tracks on similar adjacent slopes and N/NE facing obvious slide paths in the area. A good reminder that spring conditions do not equate to spring snowpack stability.