Hot summers without triple-digit heat?

 

A summer's day in Washington, D.C.

 

 

This week’s heat wave is the first of the year. While no triple-digit heat occurred, excessive heat warnings were in effect for the nation’s capital on three consecutive days as heat index or “feels-like” temperature approached 110°. Triple-digit heat is unusual in Washington, D.C. despite its frequency last year.

Washington, D.C. experienced triple-digit heat in three consecutive months last summer; June, July and August, for the first time since 2011. Before last year, no triple-digit heat occurred in the nation’s capital since 2016. Ironically, from 2016-2024 the nation’s capital had four summers that rank among DC’s Top 15 warmest. These summers featured some memorable heat waves, as described below.

2022: The hottest stretch of the summer was from July 18 – July 25.  DC’s average high/low temperatures during this eight-day heat wave were 93.25°/76.25°. Despite the hot and humid weather Washingtonians experienced, no record highs were set. The hottest temperature during this heat wave was 96° on July 23.

2021: The hottest week of this summer occurred from August 8 – August 14. This week-long heat wave saw average daily temperatures of 94.1°/72.9° in the nation’s capital. While DC’s hottest temperature during this period was 96° at National Airport, it was 100° at Dulles Airport on August 12. It’s sometimes more difficult for National Airport (DCA) to get as hot as downtown areas or inland areas since a south wind at DCA blows off the cooler waters of the Potomac River.

2020: The summer of 2020 ranks as the sixth warmest on record in the nation’s capital. There were two notable heat waves. A 20-day heat wave occurred from June 26 – July 15 when DC’s average high/low temperatures were 92°/73.8°. The hottest temperature during this 20-day period was 97° on July 3. A 7-day heat wave also occurred from July 17 – July 23. Although shorter, the heat was more intense with DC’s average daily high/low for this period being 96.4°/76.3°. It was 99° on both July 19 and July 20.

2019: A 12-day heat wave occurred from July 11 – July 22. DC’s average daily temperatures during this stretch were 93.75°/75.6°. The hottest temperature during this heat wave was 99° on July 21. There were unusually warm low temperatures at National Airport on July 20 (81°) and July 21 (80°).

Hottest summers in Washington, D.C. (Source: NOAA)

1. 81.3° - 2010
2. 81.1° - 2011
3. 80.9° - 2024
4. 80.5° - 2016
5. 80.4° - 2012
6. 80.2° - 2020
7. 80.0° - 1980
8. 79.6° - 2015
9. 79.5° - 2021, 2019
10. 79.4° - 2002, 1991
11. 79.3° - 2018, 1993
12. 79.2° - 2022, 1987
13. 79.1° - 1999, 1995, 1983
14. 79.0° - 1988
15. 78.9° - 2008, 1994, 1978, 1943