My wife and I had a great morning boarding in Mill D North Fork. For most of the morning temps were nice and cold and the new snow stayed light and powdery and everything seemed very stable. As the day wore on and the temps and sun rose, the snow started to get more damp and stick to my skins so we figured it was time to leave. We headed back to the car by taking a relatively direct route from the top of Reynolds down the South face back to the Mill D parking lot. The conditions on that aspect were about 5 inches of new snow on top of a solid and slick sun crust. As my wife descended first she initiated a small point release behind her which looked like minor sloughing of the new snow on top of the sun crust. It moved pretty slowly (never more than 10-15 mph max) but started to get wider and pick up more and more snow. It eventually caught up to her when she stopped and carried her for about 50 feet until she grabbed a small tree and it continued (still slowly) another couple hundred feet. The whole thing probably lasted more than a minute and carved all the new snow off the slope down to the sun crust. It never moved quickly or violently and didn't seem like it would have buried anybody but it would not have been pleasant had it pulled anyone over a cliff or other hazard. In retrospect we underestimated how fast the sun and rapidly warming temperatures were changing the snow conditions. We also could have chosen any number of less direct return routes to the car that would not have been nearly as susceptible to this type of activity which was clearly predicted in the morning avalanche advisory. It is interesting to note that the underlying crust was so slick it seemed that the wet snow continued sliding on slope angles that were substantially less than 30 degrees.