DC’s Dry Weather Pattern Returns

The Nation’s Capital is having another drier than average month following its first wetter than average month of 2017.  Dating back to August 2015, Washingtonians are dealing with a rainfall deficit of nearly 14” as of June 22.  That deficit is 10.34” at National Airport just since June 1, 2016.  Fortunately, the wetter than average May helped eliminate the moderate drought conditions that had enveloped parts of the DC Metro Area.

However, following a warm and dry June, May appears to have been an anomaly rather than the start of a streak of wetter than average months in the Nation’s Capital.  While the remnants of Tropical Storm Cindy brought parts of the Mid-Atlantic Region beneficial rain, the DC Metro Area saw precious little rainfall.  In fact, Washingtonians have had a total of only 1.06” of rain the entire month, compared to the June average of 3.78”.  

Acerbating this month’s dry conditions have been the warm temperatures.  While having six days with high temperatures in the 90s so far this month isn’t unusual, overnight low temperatures have been above average.  Washington, D.C. is on a streak of 14 consecutive days since the last time temperatures last fell below 70° on June 10.  That’s significant because the average low temperature doesn’t rise to 70° in the Nation’s Capital until June 28.

Area residents shouldn’t be concerned, though, about the lack of rainfall this month.  The Mid-Atlantic Region has had some exceptionally wet Junes in recent years with three of DC’s wettest June’s on record just since 2006 according to the National Weather Service.  Rainfall deficits can be made up in a hurry this time of year such as on June 25-27, 2006 when a total of 10.34” of rain occurred at National Airport.  June 2006 ultimately became the wettest June on record in Washington, D.C. (14.02”).

However, with only 1.06” of rain so far this month and no significant rain chances in the next week, this June could become one of the driest on record in Washington, D.C.  If June were to end with 1.06”, than that would make it the third driest June behind only 1940 (0.86”) and 1988 (0.95”).  Those were the only two years where June finished with less than an inch of rain in Washington, D.C.  More recently, there have been three Junes in the last 15 years that finished with less than two inches of rain.  All three were warmer than average.