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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.

Analysis of 144 U.S. cities shows that 90% have experienced increased hourly rainfall intensity since 1970, with the highest average increases in the Upper Midwest. Projections indicate that at 2°C of global warming, 85% of U.S. counties will likely see a 10% or higher increase in precipitation on the heaviest 1% of days, with disproportionate risks for Black communities and rural areas.

Analysis of 244 U.S. weather stations shows that 86% of locations have seen an increase in extremely warm winter days since 1970, with the coldest day of the year warming by an average of 7°F across 242 locations.

Analysis of 244 U.S. cities shows that winters are the fastest-warming season for most of the country, with average temperatures increasing by 3.9°F since 1970. This trend is characterized by fewer freezing nights, shorter cold streaks, and a significant increase in warmer-than-normal winter days, particularly in the Northeast and Upper Midwest. These changes threaten mountain snowpack, crop yields for the $27 billion fruit and nut industry, and the winter recreation economy, while potentially increasing pest-related health risks and allergy durations.

Climate Central analysis of 204 U.S. cities shows that the first fall freeze is arriving later in 88% of locations, delaying the date by an average of 12 days since the early 1970s. This trend extends the growing season for ragweed, prolonging allergy seasons, and disrupts ecological cues for bird migration, hibernation, and fall foliage. Additionally, the delay affects the $27 billion U.S. fruit and nut industry by reducing necessary chilling periods and allowing disease-carrying insects like mosquitoes to persist longer into the year.

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.

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%).

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.

The Union of Concerned Scientists reports that industrial agriculture is the leading cause of wetland loss over the last 250 years, which increases flood risks and releases stored carbon. In the Upper Midwest, 30 million acres of wetlands provide approximately $23 billion in annual residential flood mitigation benefits, with long-term value estimated between $323 billion and $754 billion. The document urges the US government to use the upcoming farm bill to increase funding for USDA conservation programs, such as the Conservation Reserve Program and Wetland Reserve Easements, to protect these ecosystems.

Industrial agriculture is a primary driver of wetland loss in the US Upper Midwest, where 30 million acres of wetlands provide critical flood mitigation and carbon sequestration. The report estimates that these wetlands provide nearly $23 billion in annual residential flood mitigation benefits, with long-term value between $323 billion and $754 billion. Recent legal shifts, specifically the 2023 Supreme Court ruling in Sackett v. EPA, have reduced federal protections under the Clean Water Act, leaving many wetlands vulnerable. The author argues that the next farm bill should expand the Conservation Reserve Program (CRP) cap, increase funding for the Conservation Stewardship Program (CSP) and Environmental Quality Incentives Program (EQIP), and link crop insurance to conservation practices to mitigate flood risk and support environmental justice for marginalized communities.

Climate Central's analysis of U.S. data from 1970 to 2024 shows that winter is the fastest-warming season for 74% of analyzed locations. Average winter temperatures rose by 4°F across 235 locations, with the highest warming seen in the Upper Midwest, Northeast, and Ohio Valley. The report notes a decrease in freezing nights and shorter cold streaks, alongside an increase in warmer-than-normal winter days. These trends impact western water supplies, residential energy use, the $27 billion fruit and nut industry, and the prevalence of disease-carrying pests.

Climate Central's analysis of 200 U.S. cities shows that the first fall freeze is arriving later in 85% of locations, delaying the date by an average of 11 days since 1970. This trend, alongside a 2.4°F average increase in fall temperatures across the contiguous U.S., extends growing seasons and disrupts ecological cues, leading to prolonged allergy seasons, lingering pests, and reduced yields for the U.S. fruit and nut industry.

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.

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 Great Lakes have seen a 25% decrease in basin-wide ice cover since 1973, with all five lakes experiencing shorter ice durations. This trend, mirrored across the Northern Hemisphere, is linked to warming winter air and contributes to increased lake-effect snow, altered fish species competition, and risks to cultural heritage and safety. While natural patterns like El Niño cause year-to-year variability, long-term projections suggest further ice loss and surface water warming this century.

Analysis of 240 U.S. weather stations shows that 86% of locations have experienced an increase in unusually warm winter days since 1970, with the most significant rises occurring in the Upper Midwest, Southeast, and Northeast. Winter is the fastest-warming season for 74% of the analyzed locations. These trends are accompanied by a decrease in freezing nights, shorter cold snaps, and a rise in the temperature of the coldest day of the year. The document notes that winter warming affects agriculture, water supplies, public health via allergy and mosquito seasons, and winter sports.

The U.S. experienced a record 28 billion-dollar disasters in 2023, causing over $93 billion in damages. Since 1980, tropical cyclones have been the costliest events, while severe storms are the most frequent. The document details how warming temperatures intensify specific hazards—such as increasing rainfall intensity and fueling stronger tropical cyclones—and notes that the average time between such disasters has shrunk from 82 days in the 1980s to 12 days in 2023.

Climate Central's analysis of U.S. locations from 1970 to 2022 shows that winter is the fastest-warming season for 74% of analyzed sites, with average winter temperatures increasing in 97% of locations. This warming is characterized by more warmer-than-normal days, fewer freezing nights, and shrinking cold snaps, particularly in the Northeast and Upper Midwest. These trends affect critical sectors including the $27 billion fruit and nut industry, western water supplies, and residential energy use.

Climate change is extending the freeze-free growing season in the United States, leading to longer periods of pollen exposure for nearly 20 million allergy sufferers. Analysis of 201 cities shows that 83% experienced longer growing seasons since 1970, with the most significant increases in the western U.S. Additionally, rising atmospheric CO2 levels are shown to increase the quantity and allergenicity of pollen from plants like ragweed.