2023 Fall Package

Analysis of 241 U.S. locations from 1970 to 2022 shows that fall temperatures have increased by an average of 2.4°F in 232 cities, with the most intense warming occurring in the Southwest. This trend is characterized by an increase in above-normal fall days, which prolongs risks related to heat-related illness, wildfires, and allergies, while increasing energy demand for cooling.

• Since 1970, fall temperatures have increased by an average of 2.7°F across the contiguous U.S., with the most significant warming occurring in the Southwest, Northern Rockies, and Plains regions. Specific areas experiencing at least 3.5°F of warming include all of Colorado, most of Wyoming, and parts of Arizona, New Mexico, Utah, southern California, northern Minnesota, northern Maine, and eastern Massachusetts.
• In 232 of the 241 analyzed U.S. locations, average fall temperatures have risen by an average of 2.4°F since 1970. The five locations with the highest fall warming were Reno, Nev. (7.7°F), Las Vegas, Nev. (6.1°F), El Paso, Texas (5.7°F), Tucson, Ariz. (5.3°F), and Phoenix, Ariz (5.1°F).
• The frequency of above-normal fall days has increased in 231 analyzed locations since 1970. Currently, 36% of analyzed locations (86) experience at least two more weeks of above-normal fall days than they did in 1970, and 11 locations in Nevada, Texas, Arizona, New Mexico, Florida, and California now experience 30 or more fall days above normal.
• Fall warming extends various risks, including prolonged heat-related illness for vulnerable populations, longer and more intense wildfire seasons (particularly in the western U.S.), and extended allergy seasons. It also increases energy costs and heat-trapping emissions due to higher cooling demand, allows disease-carrying insects like mosquitoes to persist longer, and can disrupt bird migrations, hibernation, and fruit ripening.

APA

Climate Central (2023). 2023 Fall Package. https://www.climatecentral.org/climate-matters/2023-fall-package

Chicago

Climate Central. 2023 Fall Package. 2023. https://www.climatecentral.org/climate-matters/2023-fall-package.

Wikipedia

{{cite report |author=Climate Central |title=2023 Fall Package |date=30 August 2023 |url=https://www.climatecentral.org/climate-matters/2023-fall-package |access-date=23 October 2026 |via=Climate Insights Directory}}

BibTeX

@techreport{climatecentral20232023, author = {{Climate Central}}, title = {{2023 Fall Package}}, institution = {Climate Central}, year = {2023}, month = aug, url = {https://www.climatecentral.org/climate-matters/2023-fall-package}, urldate = {2026-10-23}, note = {Indexed by Climate Insights Directory} }