Now that the days are shorter, the thermometer is trending downward and the holiday season is in full swing, the one thing some people in this area are wishing for, would be some snow on the ground for Christmas. Believe it or not, the National Oceanic and Atmospheric Administration (known as NOAA) literally has a definition for a white Christmas, and that would be…”To have one inch of snow on the ground at 7 a.m. on Dec. 25th”. By achieving this criteria, it is officially a white Christmas. As you can see from the historical chance for measurable snow on Christmas, the obvious is that the coast has the lowest percentage (0-10%), while the mountains and a lot of our western counties have the best opportunities of seeing snow (41-50%). Since we live in an area that can get quite cold, in tandem with having a particular storms path bring us plentiful amounts of moisture, that can sometimes lead to a whopper of a snow event. While most of the biggest recorded snowstorms have occurred after the New Year, specifically January and February, being fortunate enough to receive snow on Christmas morning can be quite the rarity; yet on occasion it can happen.
As I delved into the NWS climatology for December 25th, I found that out of 150 Christmas’ there was more than a trace of snow on the ground only ten times, with the maximum 5.4 inches of snow coming in 1962. Obviously these numbers show that there is a slim chance for a white Christmas in D.C., but SLIM is the operative word here. Looking around at other cities and towns, I came across very similar numbers to D.C., for example the most amount of snow in Sterling, Virginia was 6 inches on Christmas Day in 1969, Hagerstown saw 6.5 inches in 1909, Martinsburg, West Virginia had 6 inches in 1909 and believe it or not, Annapolis had a whopping 9.5 inches on Christmas Day, ALSO in 1909! Unfortunately for those who want snow on Christmas Day, it is slim pickings, but it seems more likely that if we get precipitation on Christmas, it is more in the form of rain than anything else. As a matter of fact, our chances of seeing rain happen, doubles compared to seeing snow in the region on Dec. 25th. So if your looking ahead, forecast models bring much colder air to the region, but the chance for the first snowflakes falling in D.C., not until the new year.