Checked: the warmest summer in U.S. history

Claim, as it reached me: “Summer 2026 was the warmest in U.S. history.” It arrived right behind July's record, and it is the kind of thing worth checking instead of repeating. I went to the source: NOAA's National Centers for Environmental Information, in its August 2026 U.S. climate report, released this week. Checked September 13, 2026. True, with two footnotes.

The numbers. June through August averaged 74.4°F across the contiguous U.S., 3.0°F above its 20th-century average. That is the warmest summer in the 132-year record (1895 to present), ahead of the previous record holders, 1936 and 2021, by 0.4°F. August closed it: 75.6°F, 3.5°F above average, the warmest August on record. Daytime highs averaged 88.6°F, also the warmest on record, and nights ran record-warm in California, Nevada, Arizona, Utah, New Mexico and Colorado.

Footnote one: which country. Same as last time, “U.S.” means the 48 contiguous states. Alaska's summer averaged 51.6°F, 1.1°F above its average, ranking only in the warmest third of its own record. The Lower 48 carried this one.

Footnote two: what else the map did. The summer was also dry overall: 8.11 inches of precipitation across the contiguous U.S., in the driest third of the record. Drought jumped from just under half of the contiguous U.S. in early August to 59.1% by September 1. The rain it did get came as extremes: Indiana and Ohio had their wettest August on record, and Hawaii had its second-wettest August (Hurricane Lala peaked at 43.54 inches at Laupāhoehoe) and its wettest January through August on record.

One claim, one source trail, plain words. If a claim is bothering you, send it to me: [email protected]. The first small one is free.

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