November - December 2010 without a doubt. We had successive snow showers which gave around 15 cm in November. On the 1st of December, a decaying snow streamer moved northwards and gave us around 15 cm. We ended up with 25 cm, with 40 cm snow drifts, temperatures on the 3rd fell to -13c here and Google weather listed the temperature for Leeds as -16c! In late December we had no snow here in east Leeds, but was very, very cold with a permanent rime frost and frozen fountains which looked stunning. The mean temperature for the entire month for me was -0.5c. 2009 - 2010 is a close second. We didn't really get any exceptional snow, around 15 - 20 cm which lasted two weeks in January, but all three winter months were colder than average. We had a white Christmas with 3 inches of snow in December 2009. February 2010 was dry and cold with a lot of ice, many pavements were treacherous and impossible to walk on. We had 3 inches one morning in late February. February 2009 was the deepest snow I had seen for a while, but the month was actually slightly above average, January 2009 was colder, the snow lasted around two weeks but only because it turned to ice very quickly. Then we have January 2004, the snow depths weren't great but I remember walking home up a steep hill, the snow was blowing horizontally into my face, proper blizzard conditions, my face was so cold to the point I almost cried!