The Start of Spring ?

Although many people consider the March 20 vernal equinox to be the official start of spring, meteorological spring began on March 1 and runs through May 31.  March is a highly variable and transitional weather much in the Nation’s Capital.  March can occasionally feature late-spring like warmth.

Average temperatures in Washington, D.C. range from 51°/34° on March 1 to 61°/42° on March 31.  The warmest March temperature on record in the Nation’s Capital is 93° on March 23, 1907.  The coldest temperature is 4° on March 4, 1873.  The difference between DC’s warmest and coldest observed March temperatures is the greatest of any month.  Over the last 10 years, there have been five warmer and five colder than average March’s.

Washingtonians average 3.48” of rain in March.  Half of the last 20 March’s were wetter and half were drier than average.  March 2006 was the driest on record in Washington, D.C. with only 0.06” of rain.  Meanwhile, March 2014 was DC’s snowiest since 1960 with 12.7”.  Snowfall records date back to the 1887-1888 winter in Washington, D.C. and in 23 of those 130 winters, March has been the snowiest month.  There is a four-way tie for the decade when March was DC’s snowiest month of the year with three in each decade (2010s, 1990s, 1940s and the 1930s).  

Not since 2008 have Washingtonians had a March without any snow.  Since February 2018 was DC’s third warmest on record according to NOAA, an earlier than average peak bloom of the famous cherry blossoms along the Tidal Basin is expected.  The National Park Service recently estimated that peak bloom will occur between March 17 – 20.  That’s compared to the average date of April 4.  The record for earliest peak bloom was March 15, 1990, while the latest peak bloom was April 18, 1958.  Some major factors that can adversely affect the cherry blossoms include episodes of very warm, very cold or very windy weather.

Being a transitional month, March often vacillates between warmer and colder than average weather in the DC Metro Area.  For example, Washingtonians had a temperature of at least 81° on four out of five days from March 27 – 31, 1998, and DC residents also enjoyed 81°/+ warmth on three consecutive days starting March 13, 2012.  In contrast, Washingtonians remained below freezing on consecutive days from March 2 – 3, 2009.  DC residents also had their snowiest St. Patrick’s Day on record in 2014 with 3.9” and a high/low temperature of only 32°/27°.