Normal January Weather ?

Frigid Temperatures in Olney, MD  (Courtesy: Carl Gottlieb)

It’s easy to lose sight of what typical January weather is like given the frigid start to 2018 in much of the country.  That includes right the DC Metro Area where temperatures have only climbed above the freezing mark three times since December 27 and once since New Year’s.  

Record lows were set this morning of -1° at Dulles Airport and 1° at BWI Airport.  The unofficial low temperature of 8° at National Airport fell short of today’s record of 5°, but is DC’s coldest January temperature since January 7, 2014 (6°) and coldest temperature, overall, since February 20, 2015 (5°).

Today’s high temperatures will remain below freezing, too, the ninth time in the last 11 days that temperatures in DC will remain at or below 32°.   However, this morning’s frigid temperatures represent the final night of record cold during this incredible stretch of bone-chilling weather.  Not only will temperatures climb above freezing tomorrow, but they are expected to climb into the 50s for the second half of the week.  

DC’s warmest January temperature on record according to NOAA is 79° that occurred on January 26, 1950.  By comparison, DC’s coldest January temperature remains the frigid -14° that occurred on January 1, 1881.  DC’s coldest January temperature since National Airport opened in 1941 is -5°, which occurred on January 17, 1982.  DC’s last subfreezing temperature occurred on January 19, 1994 (-4°). 

Some of DC’s largest snowstorms on record have occurred in January.  Today is the anniversary of a legendary DC snowstorm that occurred from January 6 – 8, 1996.  Fortunately, for those who don’t like snow, this wave of incredibly cold weather has been relatively dry without significant precipitation.

An average January features 5.6” of snow in Washington, D.C., based on NOAA data from 1981 – 2010.  Washingtonians can also expect 2.81” of rain during the first month of the year.  While nine of the last 10 January’s have been drier than average in the Nation’s Capital, four of the last 10 January’s have been snowier than average.  This can be explained by the fact that snow sometimes has a lower water content at colder temperatures.

The Nation’s Capital could use some rain or snow since drought conditions have returned for much of the DC Metro Area.  Since December 1, only 0.6” of precipitation (rain combined with liquid equivalent of the 2.7” of snowfall) fell at National Airport.  That’s on top of a stretch of 22 drier than average months in a 28-month stretch in Washington, D.C. from August 2015 through November 2017.  During that time, Washingtonians accrued a rainfall deficit of over 15”.