Was in the Y-not early on Saturday morning. Winds picked up heavy from nearly nothing during the last 30 minutes of our booter up the Y fork. We noticed wind transport happening fast, but it was confined to higher elevations/near ridges. We felt it was manageable to get into the couloir safely and once in it, it was more protected and safer. We skied close to the anchors without witnessing any snow instabilities. We went one at a time from an island of safety to the anchors, to minimize our time exposed to the cliff below and chute above. As our 3rd was nearing anchors, a large sluff/small avy hit us, and carried him over the cliff, seconds before he was able to get clipped into the anchors. After about 20 seconds of panic, he radioed up, letting us know he was okay and uninjured. (*sigh of relief*).

This avalanche was believed to be natural, as there were no other signs of parties above us. The number of sluffs releasing off the sides and following it lead us to believe it was natural as well. We tried to safely make our way down, leap frogging each other to islands of safety. Had we been more urgent about getting our 3rd person on anchors when they first arrived to us, this accident would've been entirely avoided. A good reminder that every second counts out there, and to be on point when in a high exposure situations.