An Unprecedented Feat

As the month of February enters its final days, the 2018-2019 winter season is also ending.  December 2018 and January 2019 were warmer than average months.  So far this month, February’s average temperature (combining daily high and low temperatures) is 3.4° above average in Washington, D.C.  This weekend’s rainfall will leave this month well-positioned to become DC’s third consecutive warmer and wetter than average month.

That would make this meteorological winter (comprised of the three-month period of December – February) warmer and wetter than average in the Nation’s Capital.  There have been instances where an entire winter season has finished warmer and wetter than average in DC, but not each of the months individually.  For example, last winter was warmer than average overall, but that was largely due to February 2018 that was DC’s third warmest February on record.  That was more than enough to offset a slightly colder than average (0.3°) January 2018.

The last time all three winter months were warmer than average in the Nation’s Capital was during the 2016-2017 winter season.  However, the last time DC had a wetter than average December, January and February was during the 1993-1994 winter season.  Weather records in Washington, D.C. date back to 1871.  Since then, there have been 17 winters when December, January and February were each warmer than average.  It’s worth pointing out that 10 of those winters occurred since 1990 as urbanization has continued to increase in the DC Metro Area.  By comparison, there were15 winters in the Nation’s Capital when all three months (December, January and February) have each been wetter than average.

The 2018-2019 winter is unique because December, January and February are likely to finish warmer and wetter than average.  Having a warmer or wetter than average winter sometimes hides any bitter cold or appreciable snowfall that may have occurred.  For example, this winter will also finish snowier than average with 16.6” of snow (above the seasonal average of 15.4”).  The period of January 21 – February 1, 2019 also had three days when high temperatures remained at or below 25°.  However, the warmth Washingtonians have experienced this winter has been more than enough to offset those unusually frigid days.

Wetter Than Average Winters (December, January, February) in Washington, D.C.
(Source: National Weather Service, NWS)

1.  1993-1994
2.  1978-1979
3.  1948-1949
4.  1944-1945
5.  1936-1937
6.  1932-1933
7.  1914-1915
8.  1907-1908
9.  1902-1903
10.  1901-1902
11.  1898-1899
12.  1890-1891
13.  1884-1885
14.  1881-1882
15.  1880-1881

---

Warmer Than Average Winters (December, January, February) in Washington, D.C.
(Source: NWS)

1.  2016-2017
2.  2011-2012
3.  2007-2008
4.  2004-2005
5.  2001-2002
6.  1998-1999
7.  1997-1998
8.  1996-1997
9.  1991-1992
10.  1990-1991
11.  1974-1975
12.  1973-1974
13.  1951-1952
14.  1948-1949
15.  1931-1932
16.  1889-1980
17.  1879-1880