Unfortunately, I don't keep data on snow cover retention. The best year that I recall was the winter of 1993-94. I seem to remember having continuous snow cover from about this time of year through the middle of March. We had a lot of QPF that was evenly distributed between snow, sleet, and freezing rain. It was a glacier that would not melt. I started my current job in 1997 and we've had an additional year...maybe very late 90s or early 2000s that had snow cover for many weeks. Other than that, snow cover has been elusive for any period longer than a week outside of that glorious week in February 2010. Even that only lasted about 10 days or so as I recall.