U.S. cooling demand: Summer snapshot

It’s September, and shoulder season is upon us — the perfect time to take a look back at this summer. 

What’s happening: This year’s June through August period saw a three percent decrease in nationwide cooling degree days (CDDs), compared to the same three months last year, according to the latest data from the National Weather Service (NWS). 

• Why it matters: CDDs are the primary measure of cooling demand.

Go deeper: In June, nationwide CDDs fell four percent year-over-year, but remained 11 percent above what the NWS considers normal for the month. 

• In July, CDDs rose two percent compared to last year and were nine percent above normal levels; however, they dropped again in August, by nine percent year-over-year, to eight percent below normal. 

Of note: The ‘Pacific’ region — California, Oregon, Washington — this year experienced a noticeably cooler June and July than last, according to the data, with CDDs during the months falling 18 and 47 percent year-over-year, respectively. 

• Yes, but: The trend reversed in August, with CDDs up eight percent compared to last year — and 18 percent above normal.