December was probably one of the strangest months ever for weather. The first three weeks were extremely warm, being almost 10 degrees above normal. The last 10 days cooled off, but not enough to make up for the warmth. The mean was 39.4 degrees, or 5.9 degrees above normal, and December ended up being the 10th warmest on record.
Although the month was very wet from the beginning (3rd wettest), there was also only a trace of snowfall through the 20th, and it looked like the month might end with below normal snowfall. Then 4 separate snow events dropped 14.9″ the last 10 days, making the month the 4th snowiest December of all time. Not only that, but two of the snowfalls (5.9″ and 4.9″) were two of the top 20 snowfalls for a December.
December 2012 will definitely go down as one of those months that defied expectations.