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An attribution analysis reveals that 88% of 247 major U.S. cities have seen an increase in extremely hot summer days strongly influenced by climate change since 1970. On average, these cities now experience six such days annually, compared to zero in the 1970s, with the most significant increases occurring in the South, particularly in Texas and Louisiana.

The report analyzes May 2025 temperatures across 192 U.S. cities, finding a moderate average anomaly of 0.1°F. While 102 cities were cooler than average, 24 recorded top 10 warmest May temperatures. Long-term trends show 185 of 191 analyzed stations have warmed since 1970, with Reno, Nevada, seeing the fastest increase. The Climate Shift Index (CSI) highlighted strong climate change influence in 35 cities, particularly in the West, South, and Southeast.

The report finds that human-caused climate change significantly increased the frequency and intensity of extreme heat globally from May 2024 to May 2025. Approximately 4 billion people experienced at least 30 additional days of extreme heat, and 195 countries saw the number of such days at least double compared to a world without climate change. All 67 significant heat events analyzed were influenced by climate change, with some becoming dozens of times more likely. The authors emphasize that while adaptation strategies like City Heat Action Plans are vital, comprehensive mitigation through the phasing out of fossil fuels is the only way to limit future harms.

Between 2020 and 2024, climate change increased the number of 'pregnancy heat-risk days'—days exceeding the 95th percentile of local temperatures—in every analyzed country. In 90% of countries and 63% of cities, these risk days at least doubled compared to a world without climate change. The most significant increases occurred in developing regions, particularly the Caribbean, where 15 countries saw an average of at least 60 additional risk days annually, representing roughly one-fifth of a typical pregnancy. Beyond heat, the report notes that climate-driven air pollution, flooding, and infrastructure damage further threaten maternal health and birth outcomes.

The analysis reveals a significant increase in fire weather days across much of the contiguous U.S., with the western U.S. experiencing far more frequent fire weather than the east. While the western U.S. has seen strong increases, particularly in the Southwest during spring and summer, parts of the eastern U.S. have also seen impactful increases, especially in the Southeast and Northeast. The study emphasizes that while human activity causes 87% of wildfires, fire weather primes the landscape for these fires to ignite and spread.

In April 2025, 182 out of 191 analyzed U.S. cities were warmer than normal, with an average temperature anomaly of 2.1°F. The Southeast region experienced the most significant anomalies and the highest number of days with a Climate Shift Index (CSI) of 2 or above, indicating temperatures at least twice as likely to occur due to climate change. Shreveport, Louisiana, recorded the highest anomaly at 6.33°F, while Reno, Nevada, showed the fastest long-term April warming since 1970, increasing by 8.0°F.

Climate Central analyzed 243 U.S. locations and found that 67% have already shifted to warmer planting zones between 1951-1980 and 1995-2024. Projections based on the SSP2-4.5 pathway suggest 90% of these locations will shift to warmer zones by mid-century (2036-2065), with the Upper Midwest expected to see the most significant warming.

The U.S. public EV charging network grew more than six-fold between 2016 and 2025, reaching nearly 196,000 ports. While California leads in total numbers and northeastern states lead in density, significant coverage gaps remain in the southern, central, and plains regions. To support a projected 33 million EVs by 2030, the U.S. may need 1 million additional public chargers, including 170,000 DC fast chargers.

Climate Central analysis indicates that human-caused climate change has significantly increased the risk of sub-optimal temperatures (21°C or higher) that impair elite soccer performance during the 2025 UEFA Champions League knockout stages. Comparing current data to the 1970s, the likelihood of such heat has risen for all 23 analyzed stadiums, with the most dramatic increase occurring at Lluís Companys Olympic Stadium in Barcelona, where the risk increased by 800%. This temperature threshold is critical because research shows that players cover less total distance, sprint less, and perform fewer high-intensity efforts when temperatures reach or exceed 21°C.

Analysis of NOAA data shows that all 50 U.S. states and 99% of 242 analyzed cities have warmed since 1970. Alaska was the fastest-warming state (+4.3°F), while Reno, Nevada, saw the highest city-level increase (+7.8°F). The contiguous U.S. has warmed by approximately 2.8°F, exceeding the global warming limit of 2.7°F (1.5°C). The document advocates for a clean energy transition through zero-emission vehicles, solar and wind power, and heat pumps to mitigate these trends.

The 25 most-visited national parks in the contiguous U.S. are projected to see a nearly five-fold increase in extremely hot days per year by 2050 under a 'warm wet' scenario, and up to a ten-fold increase under a 'hot dry' scenario. These trends, combined with record-breaking visitation, increase the risk of heat-related illnesses for visitors and threaten biodiversity and infrastructure. The National Park Service is implementing adaptation strategies, such as the Climate Change Response Strategy, to mitigate these risks.

In March 2025, 178 of 191 analyzed U.S. cities were warmer than normal, with an average temperature anomaly of 3.9°F. Texas and the Southwest saw the highest frequency of days where temperatures were at least twice as likely to occur due to climate change. Wheeling, West Virginia, recorded the highest anomaly at 9°F and is the fastest-warming station for March since 1970.

The analysis finds that approximately 2.5 million people and 1.4 million homes in the contiguous U.S. are at risk from a severe coastal flood by 2050 under current global carbon reduction commitments. Florida, New York, and New Jersey are the most affected states. The report highlights that older adults are disproportionately exposed, with 540,000 people aged 65 and older living in at-risk areas.

The report projects that by 2050, approximately 2.5 million people in 1.4 million homes across the contiguous U.S. will be at risk from severe coastal floods under the SSP2-4.5 pollution pathway. Florida, New York, and New Jersey face the highest risks in terms of population and housing, while Louisiana has the largest land area at risk. New York City is identified as the city with the highest number of people at risk. The analysis highlights that older adults and socially vulnerable populations are disproportionately exposed to these risks.

Analysis of 144 U.S. weather stations shows that 88% of cities experienced increased hourly rainfall intensity between 1970 and 2024, with an average increase of 15% across those locations. The highest average regional increases occurred in the Upper Midwest (+18%), Northern Rockies and Plains (+16%), and Ohio Valley (+15%). Individual cities with the largest increases include Wichita, Kansas (+38%), Reno, Nevada (+37%), Fairbanks, Alaska (+37%), and El Paso, Texas (+37%). Projections indicate that with 2°C of global warming, 85% of U.S. counties are likely to see a 10% or higher increase in precipitation on the heaviest 1% of days, with particularly high intensification expected in Alaska (43%) and Hawaii (30%).

The analysis finds that human-caused climate change increased heat-related health risks for billions globally between December 2024 and February 2025, with a significant impact on Africa.

The report finds that human-caused climate change significantly increased extreme heat and health risks globally from December 2024 to February 2025. At least 1.8 billion people experienced temperatures at least twice as likely due to climate change every day of the period, with exposure peaking at 3 billion people on February 28, 2025. Africa was particularly affected, with 293 million people experiencing 30 or more 'risky heat days' added by climate change. The analysis also highlights that 110 out of 220 analyzed countries and 287 out of 940 cities saw the average person experience strong climate influence for at least one-third of the season.

The document warns of a rare two-day 'Moderate Risk' of severe weather in the Midwest and Deep South on March 14-15, 2025, driven by temperatures 15-25°F above mid-March averages. It links this early-season warmth to human-caused climate change and notes a long-term increase in Convective Available Potential Energy (CAPE) and the frequency of extreme tornado outbreaks in the U.S.

The U.S. generated a record 756,621 GWh of electricity from solar and wind in 2024, accounting for 17% of total generation. Solar is the fastest-growing source, increasing 7.8-fold over the last decade, while wind grew 2.4-fold. Combined solar and wind generation has surpassed coal, which dropped to 15% of the electricity mix in 2024.

Climate Central's analysis of 198 U.S. cities shows that 87% have experienced longer freeze-free growing seasons since 1970, increasing by an average of 20 days. This trend, driven by carbon pollution and warming, extends the period plants release pollen, worsening seasonal allergies for millions, including approximately 19% of U.S. children. The report highlights that CO2 levels also boost pollen production, potentially increasing it by 200% by the end of the century, with disproportionate health impacts on Black and Puerto Rican children who face higher asthma risks.