Fastest-warming U.S. cities and states

Analysis by Climate Central shows that all 50 U.S. states and 99% of 242 analyzed major cities have warmed since 1970. Alaska was the fastest-warming state, while Reno, Nevada, experienced the highest city-level temperature increase. The document links these trends to rising greenhouse gas concentrations, which reached 427 ppm of CO2 in 2025, and advocates for the transition to zero-emission vehicles, solar and wind power, and heat pumps to mitigate future risks.

• Between 1970 and 2025, all 50 U.S. states experienced warming. The 49 states specifically analyzed by Climate Central saw an average temperature increase of 3.0°F, with Alaska warming the most at 4.4°F.
• Of the 242 major U.S. cities analyzed, 99% (approximately 240 cities) have warmed since 1970, with an average increase of 2.9°F. The most significant warming occurred in Reno, NV (+7.9°F), Las Vegas, NV (+6.0°F), and El Paso, TX (+5.9°F).
• Atmospheric CO2 concentrations reached 427 ppm in 2025, representing a 31% increase since 1970. This buildup of heat-trapping gases from burning fossil fuels has caused global temperatures to rise faster than at any other time in at least the last 2,000 years.
• The document identifies three primary technology sectors to reduce reliance on fossil fuels: zero-emission vehicles to address transportation (which accounts for 28% of total U.S. greenhouse gas emissions), solar and wind power to address electric power (25% of emissions), and heat pumps to address building energy use (13% of emissions).

APA

Climate Central (2025). Fastest-warming U.S. cities and states. https://www.climatecentral.org/climate-matters/fastest-warming-us-cities-and-states

Chicago

Climate Central. Fastest-warming U.S. cities and states. 2025. https://www.climatecentral.org/climate-matters/fastest-warming-us-cities-and-states.

Wikipedia

{{cite report |author=Climate Central |title=Fastest-warming U.S. cities and states |date=2025 |url=https://www.climatecentral.org/climate-matters/fastest-warming-us-cities-and-states |access-date=23 October 2026 |via=Climate Insights Directory}}

BibTeX

@techreport{climatecentral2025fastestwarming, author = {{Climate Central}}, title = {{Fastest-warming U.S. cities and states}}, institution = {Climate Central}, year = {2025}, url = {https://www.climatecentral.org/climate-matters/fastest-warming-us-cities-and-states}, urldate = {2026-10-23}, note = {Indexed by Climate Insights Directory} }