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The report finds that August 2026 saw widespread above-average temperatures across the U.S., with an average anomaly of 1.6°F across 192 cities. The Southwest was the hottest region, and 39 cities recorded one of their top-five hottest Augusts on record. Long-term trends show August warming since 1970 in 187 of the 192 analyzed locations, with Reno, Nevada, seeing the largest increase.

In July 2026, the United States experienced widespread above-average temperatures, with an average anomaly of 1.5°F across 192 cities. The Northern Rockies and Plains were the warmest region, exceeding normals by more than 4.0°F. Long-term data indicates that 185 of the 192 analyzed cities have warmed since 1970, with Reno, Nevada, showing the most significant increase. Climate attribution analysis using the Climate Shift Index (CSI) showed that San Juan, Puerto Rico, had 31 days where temperatures were at least two times more likely due to climate change.

In June 2026, the United States experienced slightly above-average temperatures, with an average anomaly of 0.7°F across 192 analyzed cities. The Southwest was the warmest region, with temperatures more than 2.9°F above normal, and Flagstaff, Arizona, recorded the most unusual warmth at 4.0°F above normal. Long-term trends show that 189 of the 192 cities have warmed since 1970, with Reno, Nevada, seeing the greatest increase of 10.6°F. Climate attribution analysis using the Climate Shift Index (CSI) indicates that San Juan, Puerto Rico, had 30 days where temperatures were at least two times more likely due to climate change.

In March 2026, the United States experienced unprecedented warmth with an average temperature anomaly of 5.8°F across 192 cities. The Southwest was the warmest region, with temperatures more than 10.4°F above normal, and Phoenix recorded the highest individual city anomaly at 12.5°F. Long-term trends show that 188 of the 192 analyzed cities have warmed since 1970, with Wheeling, West Virginia, seeing the greatest increase of 11.7°F. Climate attribution analysis using the Climate Shift Index (CSI) indicates that in Flagstaff, Arizona, temperatures on 28 days in March were made at least two times more likely due to climate change.

In February 2026, the United States experienced an average temperature anomaly of 2.1°F across 192 cities. While the Northeast was the coldest region with an average anomaly of -3.4°F, the Northern Rockies and Plains were the warmest, exceeding normal temperatures by more than 8.4°F. Long-term data indicates that 173 of the 192 analyzed cities have warmed since 1970, with Albany, Georgia, showing the greatest increase at 8.4°F. Climate attribution analysis using the Climate Shift Index (CSI) found that San Juan, Puerto Rico, had 16 days where temperatures were at least five times more likely due to climate change.

The report finds that while December 2025 temperatures in the U.S. were evenly split between warmer-than-average and cooler-than-average cities, long-term trends show nearly all analyzed cities have warmed since 1970. The Southwest was the most unusually hot region, with Casper, Wyoming, recording the highest anomaly. Climate signal (CSI) was minimal nationwide, though San Juan, Puerto Rico, saw 10 days where temperatures were at least five times more likely due to climate change.

In November 2025, the United States experienced an average temperature anomaly of 2.1°F across 194 analyzed cities, with the western half of the country seeing exclusively above-average temperatures. The Southwest, South, and Northern Rockies and Plains were the most unusually hot regions, with anomalies exceeding 4.8°F. Waco, Texas, recorded the highest anomaly at 7.5°F. Long-term trends show 183 of 194 stations have warmed since 1970, with El Paso, Texas, seeing the greatest increase of 6.9°F. Climate attribution via the Climate Shift Index (CSI) highlighted San Juan, Puerto Rico, with 27 days at CSI 5, meaning temperatures were at least five times more likely due to climate change.

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.

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.

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.

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.

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.

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.

Climate Central's analysis of 241 U.S. cities shows that 97% experienced an increase in average spring temperatures between 1970 and 2024, with an average rise of 2.4°F. The Southwest saw the most significant warming, and 80% of analyzed locations now experience at least one additional week of warmer-than-normal spring days. These trends are linked to global warming and contribute to increased wildfire risk, prolonged allergy seasons, and stressed water supplies in the western U.S.

In 2025, US solar generation increased by 83 TWh, meeting 61% of the 135 TWh rise in electricity demand. This growth was most concentrated in regions with the highest demand increases, such as Texas and the Midwest. While utility-scale solar capacity additions fell by 6% due to tariff uncertainties and grid connection delays, battery capacity surged by 133% to 26 GW, enabling solar to meet some evening demand and reducing curtailment pressure, particularly in California.

The report finds that September 2024 was unusually warm across much of the U.S., with 171 of 191 analyzed cities experiencing warmer-than-normal temperatures. While the highest temperature anomalies occurred in the Midwest and northern Great Plains, the strongest climate change signals (CSI values) were concentrated in the Southwest and Florida.

Analysis of 242 U.S. cities shows that fall temperatures have increased by an average of 2.5°F since 1970, with the most intense warming occurring in the Southwest. This trend is characterized by a higher frequency of above-normal temperature days, which prolongs risks related to heat-related illness, wildfires, and allergies, while also affecting agricultural growing seasons and energy demand for cooling.

The guide explains how climate change creates conditions for more severe and frequent wildfires in the US, while offering practical reporting tips for journalists to cover the long-term impacts, public health risks, and the role of 'good fire'.

Climate Central reports that 89% of 242 analyzed U.S. locations have seen an increase in annual 'warning days' (heat index 80°F to 94°F) since 1979, with the most significant rises in the Ohio Valley and Upper Midwest. Between 1992 and 2022, 986 U.S. workers died from heat exposure, and from 1980 to 2016, an average of 421 million work hours were lost annually, costing $14 billion. The document highlights a lack of comprehensive federal heat standards, noting that only five states have such protections, while some states like Florida and Texas prohibit local municipalities from enacting their own heat safety laws.

The report finds that June 2024 was historically hot across the United States, with climate change making temperatures 2.3 times more likely on average. The Southwest experienced the most extreme anomalies, with Nevada's temperatures being 8.2 times more likely due to climate change and the region seeing an average of 4.2 additional days above 90°F. Analysis of 191 ACIS stations showed that 12 experienced their hottest Junes on record, and 168 stations had at least one day where temperatures were at least twice as likely due to climate change.