D.C.’s April Weather Extremes

 

Having reached April’s halfway point, it’s safe to say Washingtonians have experienced a tale of two seasons so far this month.  Nine of April’s first 11 days were cooler than average in the Nation’s Capital.  This produced an average monthly temperature (combining daily high/low temperatures) that was 2.6° cooler than average as of April 12.  Dulles Airport was even cooler at 2.8°.

Since then, dramatically warmer weather arrived with highs in the 80s at Reagan National Airport on three consecutive days (April 12 – 14).  With Wednesday’s high of 86° (more typical of mid-June), April 13 became D.C.’s warmest day since September 15, 2021 (90°).  The June-like warmth the last few days has all but erased how cool the first 11 days of the month were.  D.C.’s average April temperature through April 14 is now 0.8° warmer than average, for a net swing of close to 4°. 

Although highs in the 80s don’t become “average” in the Nation Capital until late-May, April has averaged between three and four such days over the last 30 years.  D.C. has also averaged eight April days with highs in the 70s in that time.  However, highs in the 90s are rare in Washington, D.C. as are lows in the 20s during the month of April, with each occurring roughly twice every 5 years since the early 1990s.

April 2022 had a rainy first half in the Nation’s Capital with measurable rainfall on seven of the first 14 days.  With a rainfall total of 2.81” at April’s halfway point, D.C. is only 0.40” from its monthly average of 3.21”.  There has been a lot of variability in April rainfall in the Nation’s Capital over the last decade.  Two of D.C.’s 10 wettest April’s occurred just since 2014.  Meanwhile, six of the last 10 April’s have been drier than average.

Whether or not April is wetter than average in the Nation’s Capital has little bearing on what the entire spring will be like.  For example, D.C. had a rainfall surplus of 3.26” in April 2014, consistent with a combined rainfall surplus of 1.78” for March and May in 2014.  Meanwhile, Washingtonians had an April 2020 rainfall surplus of 3.09”, but a combined rainfall deficit of 2.47” for March and May.  NOAA’s Climate Prediction Center expects warmer than average weather for much of the second half of April combined with below average rainfall in the D.C. Metro Area.