Snow in March?

March snow in the DC Metro Region  (March 4, 2016)

Although less common than in January and February, Washingtonians do see snow during March.  National Weather Service data indicates that the Nation’s Capital averages 1.3 inches of March snow.  In fact, above average snowfall has occurred during three of the last four years in the Nation’s Capital.

March is a transitional weather month with a big change in daily average temperatures in Washington, D.C.  The average high on March 1 is 51 degrees, while it climbs to 61 degrees by March 31.  There’s also an increased amount of daylight: sunrise and sunset on March 1 are 6:38 AM / 6:02 PM, while on March 31 they are 6:52 AM / 7:31 PM.  These elements conspire to make significant snowfall in the Nation’s Capital relatively rare in March.

Just two years ago, Washingtonians had a snowy St. Patrick’s Day and with a total of 12.7 inches, March 2014 was the snowiest March since 1960.  It was also the snowiest March on record at Dulles Airport where 19.8 inches accumulated.  Large temperature fluctuations are also common in March shortly before or after it snows.  For example, on March 15, 2014, the high at National Airport was 70 degrees and the snow began falling on the evening of March 16.  According to the National Weather Service, it was back up to 61 degrees on March 20, 2014 – just three days after the 7.2 inches of snow concluded.  So while March snowfall can be significant, it doesn’t usually last long because of the changeable weather.

Washington, D.C.’s largest March snowstorm on record came on March 27 – 28, 1891 when 12.0 inches occurred.  The largest March snowfall since National Airport opened in June 1941, was when 11.5 inches accumulated on March 28 – 29, 1942.  When the 7.2 inches fell on March 16 – 17, 2014, that became the tenth largest March snowfall on record in the Nation’s Capital – and bumped to the “Superstorm of 1993” (that brought Washington, D.C. 6.6 inches of snow) to number eleven.

Although this month has been 8.6 degrees warmer than average through March 18, the next few days will be more winter-like with temperatures falling through the 40s this afternoon and highs only in the 40s tomorrow and Monday.  That’s following yesterday’s high temperature of 67 degrees and is also ironic because tomorrow is the vernal equinox and first official day of spring.  Most of the DC Metro Region with see some snow this afternoon continuing into tomorrow in spots.  Slushy accumulations are possible in grassy areas and on rooftops primarily west and north of town.  However, roads should remain just wet since ground temperatures are well above freezing.  Follow my colleagues and me on the WUSA9 weather team for the latest weather updates.