Hottest and Coldest Temperatures Ever in Washington DC on September 21

On September 21st in Washington, D.C., the weather varied throughout the years. The hottest temperature ever recorded for this date was 91.9°F in 1965, while the coldest temperature was 41.0°F in 1956. The average temperature for this day is 69.28°F, with an average high of 73.58°F and an average low of 64.98°F. In 1965, when the highest temperature was recorded, an intriguing news item was the opening of the Astrodome in Houston, Texas, the world's first indoor air-conditioned stadium which played a significant role in the evolution of sports venues.