Summer 2023 Was 15th Hottest on Record Although Population Weight CDD Were Diminished

Discussion: In the U.S., meteorological summer was the 15^th hottest on record from the 1895-2023 climatology. Featured was all-time-record heat in Louisiana (Fig. 1). The entire Southern U.S. and Northwest States observed all-time top ten hot summer seasons. Interestingly, the U.S. population weight CDD for summer 2023 was not nearly as impressively hot. The warm season started with the coolest national CDD totals in the 2000-2023 climatology, was followed by the 10^th hottest July since 2000 (and not as hot as the past 3 years) and finished with moderate demand for AUG/SEP also somewhat cooler than the past several years (Fig. 2). The issue? The anomalous hot weather did not attack the high population Northeast U.S. Corridor.

Fig. 1: NOAA state rankings for temperature during the meteorological summer 2023.

Fig. 2: U.S. population weight cooling degree day rankings for 2000-23 by month of the warm season for the past 4 summer seasons.