Monthly Attribution Overview - June 2025

In June 2025, the United States experienced an average temperature anomaly of 1.5°F across 192 analyzed cities, with the Ohio Valley region showing the highest regional anomaly at 2.18°F. The analysis indicates a strong climate change influence, with 78 cities experiencing at least one week of Climate Shift Index (CSI) values of 2 or higher. Long-term data shows that 190 of 191 analyzed stations have seen positive June warming trends since 1970, with Reno, NV, experiencing the most significant increase at 7.2°F.

• Across 192 analyzed cities in the U.S., the average temperature anomaly for June 2025 was 1.5°F, with 166 cities recording hotter-than-average temperatures. The Ohio Valley region—including West Virginia, Tennessee, Ohio, Illinois, Missouri, Indiana, and Kentucky—was the most unusually hot region with an average anomaly of 2.18°F, while the West had the smallest anomaly at 0.37°F.
• Climate change significantly influenced June 2025 temperatures, as evidenced by 78 cities experiencing at least seven days with a Climate Shift Index (CSI) of 2 or higher. The Southwest region had the highest average number of such days at 14. Specifically, Honolulu, Hawaii, recorded 23 days at CSI 5, meaning temperatures on those days were at least five times more likely due to climate change.
• Long-term warming trends since 1970 are evident in nearly all analyzed locations, with 190 out of 191 ACIS stations showing positive temperature trends for June. Reno, NV, exhibited the fastest warming, with its average June temperature increasing by 7.2°F since 1970.
• Raleigh, NC, was identified as the most unusually warm city in June 2025, with a temperature anomaly of 4.92°F.

APA

Climate Central (2025). Monthly Attribution Overview - June 2025. https://www.climatecentral.org/report/monthly-attribution-overview-june-2025

Chicago

Climate Central. Monthly Attribution Overview - June 2025. 2025. https://www.climatecentral.org/report/monthly-attribution-overview-june-2025.

Wikipedia

{{cite report |author=Climate Central |title=Monthly Attribution Overview - June 2025 |date=1 July 2025 |url=https://www.climatecentral.org/report/monthly-attribution-overview-june-2025 |access-date=23 October 2026 |via=Climate Insights Directory}}

BibTeX

@techreport{climatecentral2025monthly, author = {{Climate Central}}, title = {{Monthly Attribution Overview - June 2025}}, institution = {Climate Central}, year = {2025}, month = jul, url = {https://www.climatecentral.org/report/monthly-attribution-overview-june-2025}, urldate = {2026-10-23}, note = {Indexed by Climate Insights Directory} }