Here are some key stats from the past month and the summer overall:
- August’s average temperature was 80.1 degrees in Washington, exactly 2 degrees warmer than the 30-year average and the 13th hottest on record (0.9 degrees cooler than last year).
- August rainfall was only 1.99 inches, 0.94 inches drier than normal and the 34th driest of all-time (and 3.2 inches drier than last year); this was the driest single month since March 2018′s 1.92 inches.
- The summer’s temperature averaged 79.5, 1.8 degrees hotter than normal and the seventh-hottest summer ever recorded.
- The summer’s rainfall was 12.75 inches, 2.31 inches above normal, but 7.38 inches drier than last summer.
The hottest, coolest and wettest weather observed during August is summarized below:
A few records were matched or surpassed in August, highlighted by the heat on Aug. 19, when all three local airports set record highs:
- Dulles logged a record rainfall of 2.18 inches on Aug. 15, besting 1.74 from 1976.
- Baltimore tied the Aug. 18 record high of 98 from 2002.
- Washington tied the Aug. 19 record high of 98 from 2002.
- Dulles tied the Aug. 19 record high of 95 from 2002.
- Baltimore set a record high of 99 on Aug. 19, surpassing 1914′s 97.
The prevailing weather pattern
One of the big issues for August was the loss of El Niño influences, which often increase our rainfall potential. The Tropical Pacific cooled from late July to early August, and the atmospheric response brought less moisture to Washington, resulting in its first drier-than-normal month since April.
The overall weather pattern over the Lower 48 states favored heat in the West, South, and East with a cool patch in the north central United States.
How was our forecast for August?
In our outlook for August, we predicted a hotter and wetter than normal month, and we were only half-right.
Temperatures were hotter than normal again (for the fifth month in a row), while rain was below normal for the first time since April.
This forecast earns a grade of C+, since it was dry but not super dry (Baltimore was drier than normal, but Dulles was wetter than normal).
Jason Samenow contributed to this article.