The contiguous United States experienced its hottest month on record in July, according to data released by the National Oceanic and Atmospheric Administration (NOAA). The average temperature across the Lower 48 states was 76.89 degrees Fahrenheit (24.94 degrees Celsius), exceeding the previous record set in July 1936 by a narrow margin.
This record-breaking heat blanketed most of the continental U.S., with the most extreme temperatures observed in the Mountain West, Southwest, Northern Plains, and Southeast. Every state in the contiguous U.S. was at least 1 degree Fahrenheit warmer than the 20th-century average for July. While Alaska experienced cooler-than-normal conditions, the overall trend for the Lower 48 was significantly hotter.
Scientists attribute the current extreme heat to the burning of fossil fuels, such as coal, oil, and gas. This contrasts with the Dust Bowl era heat, which was more localized and exacerbated by agricultural practices at the time. Experts note that the current widespread heat is consistent with the projected impacts of climate change.
A key factor contributing to the record was the unusually high nighttime low temperatures, which surpassed the previous record for hottest minimums by 0.7 degrees Fahrenheit. Scientists highlight that warmer nights are a classic indicator of human-caused climate change, as they provide less relief from daytime heat and increase overall heat stress. Studies indicate that prolonged exposure to high nighttime temperatures can lead to increased mortality and sleep disruption.
Looking at longer-term trends, the summers of 2021 and 1936 are tied for the hottest on record for the contiguous U.S. Through July of the current year, 2026 is slightly cooler than 2021, which was driven by record heat in June. Some climate scientists suggest that in the context of ongoing climate change, current years might represent some of the coolest experienced in the future.
To address these trends, experts recommend a significant reduction in fossil fuel consumption and investment in adaptation strategies to cope with the evolving climate.