It is true that the NOAA predominantly puts out winter forecasts for the conus that are mostly AN. That may not verify but I can understand why they do. I would say your AN or near normal snowfall this year was more a matter of luck. Not that ORD hasnt had a run of AN snowfalls the last 10 years. Will see but I think it will become increasingly difficult for the pattern to line up for persistent cold rather then persistent warm. I also think you are going to keep hearing more often in subsequent winters,"If only we had some cold air to work with this system would have been great."