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A heat event in the Western U.S. from July 8-11, 2025, is forecast to bring temperatures 5-12°F above normal, with human-caused climate change making the event at least three to five times more likely for tens of millions of people.

Climate Central analysis finds that human-caused global warming increased the maximum wind speeds of every Atlantic hurricane in 2024 by 3 to 14 mph. This intensification was driven by record-breaking sea surface temperatures, which were made up to 800 times more likely by climate change. The report specifically highlights that major hurricanes Helene and Milton were strengthened by 10 mph and 8 mph respectively, and that three hurricanes were pushed into higher Saffir-Simpson categories due to this warming.

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.

Climate Central analysis indicates that human-caused climate change has made the extreme heat gripping Spain and southern France in June 2025 at least five times more likely. Temperatures are forecast to reach up to 40°C, with approximately 94% of Spain's population expected to experience at least one day of exceptional climate-driven heat.

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.

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.

A study by World Weather Attribution found that human-induced climate change made a March 2025 heatwave in Central Asia approximately 4 °C hotter and three times more likely. The event saw temperatures exceeding 30 °C even at 1000m altitude, affecting regions including Kazakhstan, Uzbekistan, Turkmenistan, Tajikistan, and Kyrgyzstan. The analysis notes that climate models underestimate the recent increase in March temperatures, meaning the reported influence of climate change is a conservative estimate. The heatwave coincided with critical agricultural periods, such as the sowing of spring wheat in Kazakhstan and the flowering of export fruit crops, potentially impacting yields in a region where agriculture employs up to 50% of the workforce.

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.

In February 2025, U.S. temperature anomalies were split, with 92 cities warmer and 99 cooler than the 1991-2020 normal. Despite an average anomaly of -0.3°F and significant cold in the Northern Rockies and Plains, no city set a low temperature record for the month. Conversely, Phoenix, Arizona, recorded its hottest February on record. Analysis using the Climate Shift Index (CSI) indicates that temperatures in many cities remained warmer than they would have been without climate change, as more cities experienced days with positive than negative CSI values. Long-term trends show that 189 out of 191 analyzed stations have warmed since 1970, with Juneau, Alaska, being the fastest-warming station for February.

In February 2025, Brazil experienced a record heatwave where temperatures reached up to 44°C, affecting over 170 million people. The event, linked to climate change, caused significant public health strain in Rio de Janeiro, water shortages in favelas, and school delays in Rio Grande do Sul.

A marine heatwave has affected the west coast of Australia since September 2024, with over 60% of the analyzed region meeting heatwave criteria by early January 2025. The most affected area is off the northwest coast, where temperature anomalies exceeded 1.5 degrees Celsius and some locations remained in a heatwave state for over 120 days. Analysis using the Ocean Climate Shift Index indicates that climate change made these daily ocean surface temperatures at least 20 times more likely on average, with likelihood increasing over 100 times during late November.

In December 2024, 166 out of 191 analyzed U.S. cities were warmer than normal, with the most significant anomalies occurring in Montana. While long-term warming trends are evident—with 189 of 191 stations showing positive trends since 1970—daily climate attribution via the Climate Shift Index (CSI) remained generally low, though specific cities in Puerto Rico, Hawaii, and Alaska saw several days where temperatures were significantly more likely due to climate change.

In January 2025, 166 out of 191 analyzed U.S. cities were cooler than normal, with the Ohio Valley and Southeast particularly affected. Despite these cool anomalies, no city set a low temperature record for January, and the warming influence of climate change remained pronounced. Alaska was the warmest state, with Fairbanks recording the highest anomaly at 14.6°F above normal. Analysis using the Climate Shift Index (CSI) showed that days where warmer temperatures were made at least twice as likely by climate change outnumbered days where cooler temperatures were made twice as rare.

The report finds that human-induced climate change significantly increased the frequency and intensity of extreme heat globally from May 2024 to May 2025, affecting billions of people and making all 67 identified significant heat events more likely. It highlights the disproportionate impact on vulnerable populations and the systemic failure to accurately document heat-related mortality, while advocating for a combination of urban heat action plans and aggressive fossil fuel mitigation.

Climate Central's Ocean CSI analysis indicates that Cyclone Chido intensified over waters made significantly warmer by human-caused climate change, with some temperature spikes being up to 92 times more likely due to global warming.

Climate change is significantly increasing the number of winter days with minimum temperatures above 0°C across the Northern Hemisphere. Analysis of the decade 2014-2023 shows that over one-third of analyzed countries and 44% of analyzed cities experienced at least one additional week of above-freezing days annually. Europe is the most affected region, with some countries like Lithuania and Latvia seeing over 20 additional above-freezing days per year. These shifts impact snowfall, the USD 12.5 billion winter sports industry, water supplies, and ecosystem health.

Climate change increased the maximum wind speeds of every Atlantic hurricane in 2024 by 3 to 14 mph, with some storms moving into higher Saffir-Simpson categories. The analysis, based on a rapid attribution framework, found that human-caused global warming elevated ocean temperatures by as much as 2.5°F, making elevated sea surface temperatures in hurricane tracks up to 800 times more likely.

In November 2024, the Western Pacific saw a record four simultaneous named tropical systems—Typhoon Yinxing, Typhoon Toraji, Super Typhoon Usagi, and Super Typhoon Man-Yi—all of which experienced rapid intensification due to warmer-than-average sea surface temperatures. Analysis using the Climate Shift Index: Ocean indicates these temperatures were made up to 40 times more likely by human-caused climate change. The Philippines was severely affected by 16 tropical cyclones or their remnants this season, resulting in at least 160 deaths and the displacement of over 9 million people due to flooding, landslides, and infrastructure damage.