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The document explains that rising global temperatures increase 'atmospheric thirst,' where the atmosphere absorbs more moisture from the land. In the western U.S., this heat-driven demand has replaced lack of precipitation as the leading cause of exceptional drought since 2000, contributing to a multi-decade megadrought in the Southwest and increasing wildfire risk in California and Nevada.

The October 2025 briefing reports that global temperatures remained exceptionally high, with the month ranking as the third warmest on record. In the U.S., warming fall temperatures have delayed the first freeze in 88% of analyzed cities, while significant drought persists across 67% of the contiguous U.S. despite localized heavy rainfall in Southern California.

Climate Central's analysis for June to August 2025 reveals that at least 22% of the global population experienced temperatures made at least twice as likely by climate change daily. In the U.S., over 21 million people in 32 cities faced 30 or more 'risky heat' days added by climate change, with some cities, such as Honolulu, seeing all their risky heat days attributed to human-caused warming.

The Union of Concerned Scientists and a broad coalition of experts argue that the EPA's proposal to repeal the 2009 Endangerment Finding is contrary to scientific evidence and the public interest. They assert that human-caused climate change is indisputable and causes severe harms to public health, the economy, and the environment. The authors specifically criticize the EPA's reliance on a Department of Energy report they describe as unscientific and inaccurate, while urging the agency to maintain regulations on heat-trapping emissions to meet global climate goals.

August 2025 was the third warmest August globally on record, with all ten warmest Augusts occurring since 2015. In the United States, 98% of analyzed cities have experienced fall warming, and as of September 9, at least 60% of the country faces abnormally dry or drought conditions. A record-breaking marine heatwave in the North Pacific Ocean, attributed to climate change, is expected to persist into October.

August 2025 in the United States was generally cooler than normal, with an average anomaly of -0.5°F across 196 cities, though 189 of those cities have shown long-term August warming trends since 1970. Despite the monthly average, 27 cities experienced at least two weeks of Climate Shift Index (CSI) values of 2 or higher, and San Juan, Puerto Rico, saw 28 days at CSI 5, indicating a strong climate change influence on those specific days.

Climate Central argues that the Department of Energy (DOE) report, “A Critical Review of Impacts of Greenhouse Gas Emissions on the U.S. Climate,” fails to represent the scientific consensus and should not serve as a policy basis. The organization asserts that the DOE report selectively ignores two decades of scientific developments and omits major international assessments. Specifically, Climate Central contends that the DOE understates the link between human-caused climate change and the increasing intensity, rainfall, and rapid intensification of hurricanes, as well as the acceleration of sea-level rise. It further argues that the DOE's analysis of temperature extremes is misleading by focusing on the 1930s Dust Bowl era without global context and that its assessment of wildfires in the western U.S. is incomplete. Finally, the document disputes the DOE's claims regarding solar variations and the validity of extreme event attribution (EEA) methodologies, while arguing that the DOE's use of GDP to downplay disaster costs ignores the increasing physical hazards of climate change.

A research paper by World Weather Attribution finding that climate change made the extreme fire weather conditions of 2025 in Türkiye, Greece, and Cyprus approximately 10 times more likely and significantly more intense.

An event attribution study by World Weather Attribution found that human-induced climate change, primarily from fossil fuel combustion and deforestation, has increased the intensity of 30-day maximum rainfall in northern Pakistan by approximately 15%. The study highlights that while the event had a return period of about five years, the resulting high death toll—300 fatalities nationwide as of August 3, 2025, including 140 children—was exacerbated by rapid urbanization, informal settlements, and poor building code enforcement. The report emphasizes a significant funding gap for adaptation, noting that Pakistan requires US$152 billion for adaptation between 2023 and 2030, much of which remains unfinanced.

A forecast for extreme heat across the Southwest U.S. and northern Mexico indicates temperatures up to 18°F above normal, with the Climate Shift Index (CSI) attributing a level 5 likelihood to human-caused climate change. Approximately 53 million people are expected to be affected by these conditions, which are compounded by persistent drought in the region.

In July 2025, the United States experienced an average temperature anomaly of 1.4°F across 196 analyzed cities, with the eastern half of the country seeing above-average temperatures. The Ohio Valley was the most unusually hot region, while the West was the only region cooler than normal. Long-term data indicates that 189 of the 196 cities have seen warming trends since 1970, with Reno, Nevada, experiencing the most significant increase. Climate change influence was particularly strong in the Southeast and in San Juan, Puerto Rico, where 19 days reached a Climate Shift Index (CSI) of 5.

Using Google Search data, the Yale Program on Climate Change Communication identifies that interest in climate change in the United States follows predictable cycles tied to Earth Day and the school year, as well as spikes driven by extreme weather. While heatwaves trigger nationwide interest, events like wildfires produce more localized spikes based on geographic exposure, such as the 2023 Canadian wildfires affecting the American Northeast. The authors argue that these trends can be used by decision-makers to time communications on risk, adaptation, and the transition to renewable energy when public awareness is highest.

The study analyzed rainfall events in Colombia and Venezuela, finding that the June 2025 floods were not meteorologically extreme, with return periods of 10 and 3 years respectively. While some data suggests a slight decrease in rainfall likelihood and intensity in a cooler climate, high uncertainty remains due to model disagreement and a lack of high-quality in-situ weather data in northern South America. The report emphasizes that vulnerability is exacerbated by informal urbanization, deforestation, and socio-economic instability, necessitating increased investment in weather monitoring and climate resilience to manage both droughts and intense downpours.

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.

A rapid analysis by World Weather Attribution finds that climate change made a June 2025 heatwave in southeast England approximately 2-4°C more intense, increasing the likelihood of such an event from once every 50 years to once every 5 years. The report highlights that early-season heatwaves are particularly dangerous due to a lack of human acclimatisation and that the UK's building stock, designed for heat retention, exacerbates indoor overheating. While the Heatwave Plan for England provides a foundation for response, the Climate Change Committee notes that heat-related policies remain fragmented and lack long-term targets.

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.

Analysis of 247 U.S. cities shows a significant increase in sweltering summer nights influenced by climate change, with average annual occurrences rising from one in the 1970s to approximately 27 currently. Nighttime temperatures have risen by an average of 3.1°F across 231 analyzed locations, with the Southwest experiencing the highest regional warming and Florida cities seeing the largest increases in climate-fueled warm nights.

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.