Left the hair pin skinning on 4” of new wet-soft snow left over from the night before. Our goal was a quick ski if the Coulior under the Pika Peak snowfield. As we ascend, the skinning was tough caused by the new snow on the old crust. We pressed on with sights set on some higher open faces, then it started to rain the top layer of snow changed noticeably. As we were close to our objective Coulior we decided to ski it rather than the gully and open face we ascended. As we skied towards the bowl before the col. we noticed reactive snow under skis and boards. At the roll over we decided to ski cut above the line letting lose a slide that was approx 30ft wide and slid for ~80-100ft vert. As we approached the intended line it appeared to have already triggered naturally earlier in the day. Dicey conditions that changed from meh to worse with time.