D.C.’s Wettest July Day’s

 

July is the wettest month of the year in the Nation’s Capital according to NOAA, with a monthly rainfall average of 4.33” based on the 30-year period of 1991-2020.  In recent years, July has been a particularly wet month.  Over the last five years, the Nation’s Capital has had nine July days with at least an inch of rain, including four days with at least 3” of rain.  That includes yesterday’s 4.05” at National Airport. 

Yesterday’s rain fell short of D.C.’s July 9 record of 4.69” set in 1970, but it was D.C.’s rainiest day since September 30, 2010 (4.66”).  Yesterday’s heavy rain was localized as Dulles Airport saw only 1.48” and BWI Airport saw a July 9 record of 1.36”.  July isn’t usually an active month in the tropical Atlantic so most of this rainfall occurred absent any influence from a tropical system.

D.C.’s 10 Wettest July Days (Source: NOAA)

1. 4.69” (July 9, 1970)
2. 4.35” (July 22, 1969)
3. 4.25” (July 30, 1878)
4. 4.12” (July 30, 1876)
5. 4.05” (July 9, 2022)
6. 4.00” (July 21, 2018)
7. 3.68” (July 5, 1908)
8. 3.44” (July 8, 2019)

9. 3.37” (July 13, 1922)
10. 3.31” (July 28, 2017)

D.C.’s Rainiest July days since 2017 (Source: NOAA)

1. 3.31” (July 28, 2017)
2. 4.00” (July 21, 2018)
3. 2.79” (July 17, 2018)
4. 3.44” (July 8, 2019)
5. 2.04” (July 7, 2020)
6. 1.89” (July 23, 2020) à third wettest July 23
7. 1.27” (July 1, 2021)  à not top 3
8. 1.15” (July 9, 2021) à 2022 rainfall makes this D.C.’s fourth highest July 9 total
9. 4.05” (July 9, 2022)