Putting March 2018 Into Perspective

March 2018 will finish as cooler than February in Washington, D.C. for a second consecutive year.  That’s the first time it’s happened in consecutive years since 1890-1891.  Through March 29, DC’s average monthly temperature (combining daily high and low temperatures) is 42.8° (well below the March average of 46.8°). 

The first 60°/+ temperature of the month didn’t occur until yesterday when the high temperature reached 78° at National Airport.  That’s the second latest first 60° March day in the Nation’s Capital on record.  Ironically, January and February each had eight days when high temperatures reached at 60° or warmer.

While no record cold occurred in the Nation’s Capital this month, the cooler than average weather was very persistent.  High temperatures have been below average on 23 days since March 1.  Washingtonians also had more days in March where low temperatures were at or below freezing (eight) than February (six).

February was warmer than average in both 1890 and 1891 in the Nation’s Capital and March was considerably cooler average.  However, February 2017 and February 2018 were not only warmer than average, but were DC’s warmest and third warmest February’s on record.  March 2017 was 0.4° warmer than average, but still finished 0.5° cooler than February 2017 because the month was so warm in Washington, D.C.  By comparison, this March has been significantly cooler than average in Washington, D.C.  Consequently, there will be a much larger difference in temperature between the average monthly temperatures of February (45.3°) and March 2018 (42.8°). 

DC’s warmest temperature so far this month occurred yesterday (77°) while March’s coldest temperature (31°) occurred four times.  The high temperature of 36° on March 21 was significantly below the average high of 58°.  It was DC’s coldest high temperature since February 3 (also 36°).  March’s cooler than average temperatures have caused the National Park Service to push back the dates of the expected peak bloom of the cherry blossoms on the Tidal Basin to April 8 – 12.  Peak bloom is defined as when 70% of the blossoms are out.

March 2018 will finish as a snowier than average month (4.5” is more than triple DC’s March average of 1.3”).  However, this month will finish with below average rainfall with only 1.92” of rain (that includes liquid equivalent of the snowfall) since March 1 in Washington, D.C.  That’s not unusual since 10 of the last 20 Marchs have been drier than average in Washington, D.C.  However, March 2018 is the sixth consecutive March that Washingtonians have had measurable snowfall.  The Nation’s Capital has also had above average snowfall in five of the last six Marchs (including this month).