Ranking DC’s July heat

 

Washington, D.C. went from seeing no triple-digit heat for nearly eight years before it finally reached 100° on June 22. That helped last month finish as DC’s second warmest June on record and was a harbinger of what was to come.

July not only picked up where June left off, but will finish as one of DC’s warmest July’s on record. That’s due to two separate stretches of record-setting heat. The first was from July 4 – July 11 when DC’s average high/low temperature was 97°/78.38°. Although no triple-digit heat occurred, highs ranged from 95°-99° on seven of these eight days. 

Next, highs reached 101°/+ on four consecutive days for the first time from July 14 – July 17. New record highs of 101° and 102°, respectively, were set on July 14 and July 15 at National Airport. A record-tying high of 104° also occurred on July 16.

Making this month particularly hot is how warm the overnights have remained with lows at or above 80° on six days. Seventeen of the first 21 days of July were warmer than average and that coincided with unusually dry weather. Only 1.09” of rain fell at National Airport through July 21. However, the final 10 days of the month have been cooler and wetter downtown with 3.21" of rain. 

Those cooler than average days are what will ultimately keep this July from finishing as DC’s warmest on record. With an average temperature of 83.7° as of July 30, this month will finish as the fourth warmest on record. That will also make July 2024 the seventh Top 10 warmest to occur just since 2010.

DC's Warmest July's (Source: NOAA)

1. 84.5° (2011)
2. 84.0° (2012)
3. 83.9° (2020)
4. 83.7° (2024)
5. 83.1° (2010, 1993)
6. 83.0° (1999)
7. 82.7° (2016)
8. 82.6° (1987)
9. 82.3° (1980)
10. 82.1° (2019, 1955)