July was the hottest month in U.S. history on record

July shattered temperature records across the United States, officially becoming the hottest month since records began. The contiguous U.S. experienced an average temperature of nearly 25 degrees Celsius (76.9 Fahrenheit), according to the National Oceanic and Atmospheric Administration (NOAA).

This figure represents a significant departure from the norm, sitting 1.8 degrees Celsius (3.3 Fahrenheit) above the 20th-century average. NOAA data indicates this July surpassed previous record-holders, July 1936 and July 2012, by a margin of 0.06 to 0.11 degrees Celsius (0.1 to 0.2 Fahrenheit). Both daytime high temperatures and nighttime low temperatures were well above historical averages, with nighttime lows setting a new record for the month.

The extreme heat was widespread, impacting nearly all of the contiguous U.S. The interior West, Southwest, Rockies, Northern Plains, and Upper Midwest saw temperatures far exceeding average levels. This widespread heatwave follows a pattern of record-breaking warmth, as the previous month, June, was the second hottest on record for North America, Europe, and Africa.

Compounding the heat, the western and southwestern U.S. endured their warmest first half of the year on record, coupled with significantly below-average rainfall. By July, drought conditions affected approximately 48.5% of the contiguous U.S. NOAA also noted that the developing El Niño phenomenon is expected to be one of the strongest on record, potentially leading to drier conditions and warmer winters.