Climate Central

New Climate Central analysis shows that human-caused climate change is the leading driver of fall warming trends in 82% of 245 major U.S. cities analyzed from 1970-2025. September 1 is the start of meteorological fall. The season has warmed in every county across the contiguous U.S. since 1970 — and is warming fastest in the Southwest. Fall has warmed in 241 U.S. cities — by 2.9°F on average from 1970 through 2025.

Aug. 18, 2026 Climate change is supercharging the water cycle, bringing heavier rainfall extremes and higher flood risk across the United States. A warmer atmosphere holds more moisture, increasing the odds of heavier downpours and flash flooding. Over the past two weeks, multiple communities have been impacted by repeated thunderstorms tied to a stalled front, trapped beneath a heat dome. Meanwhile, Hawaii experienced flooding from a tropical system boosted by unusually warm ocean waters.

Aug. 10, 2026 The Pacific is experiencing a historic marine heat wave — but it’s far from alone. Every major ocean basin across the globe is currently experiencing unusually warm sea surface temperatures driven by climate change. Pacific Ocean The Pacific continues to host the world’s largest marine heat wave, now covering 63 million square kilometers — about 17% of Earth's oceans — an area larger than North and South America combined.

Hot summer nights limit our ability to cool off and recover from extremely hot summer days. This can lead to higher heat stress, disrupted sleep, and related health risks. New analysis shows that the number of unusually warm summer nights has risen since 1970 in 95% of 243 major U.S. cities. On average, these cities now experience 24 more such nights each summer than they did in the early 1970s.

View guidelines for use of these broadcast-ready news packages. BY BEN TRACY, SENIOR CLIMATE CORRESPONDENT ON ASSIGNMENT FOR CLIMATE CENTRAL As firefighters battle fast moving wildfires near Spokane, Washington, thousands of residents have been forced to evacuate, homes have been destroyed, and thick smoke has blanketed parts of the Inland Northwest. The fires are the latest reminder that when a wildfire is detected can be just as important as where it starts.

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Demand for cooling is rising across the U.S., contributing to higher energy bills as households rely more on air conditioning in our warming climate. Cooling degree days — a temperature-based metric used to estimate the demand for energy to cool buildings — have increased since 1970 in 97% of the 241 major U.S. cities analyzed by Climate Central. Based on long-term trends in cooling degree days, these cities have seen a 37% increase in cooling demand, on average, since the early 1970s.

July 24, 2026 Human-caused climate change is fueling dangerous heat across much of the United States as a prolonged heat wave spreads from the western U.S. eastward to the Midwest and South. Climate Shift Index levels of 5 — the highest possible — are forecast across large areas of the country through July 28, indicating that climate change made the extreme heat at least five times more likely. Over two dozen states are forecast to experience temperatures above 100°F (38°C).

Mosquito bites are a nuisance and a health risk. As the climate warms, mosquitoes can emerge earlier in the year and spread diseases over a longer season. Climate Central analyzed the changing annual frequency of mosquito disease days in 239 major U.S. cities from 1970 to 2025.

Sufficient sleep quality and duration are essential for people’s health and well-being, but hotter nighttime temperatures are making it harder for people to get the rest they need. Globally, the average person lost nearly 56 hours of sleep per year due to high ambient temperatures during the 2020-2025 period, according to a new analysis from Climate Central. Cities across the Middle East experienced the highest levels of climate change-attributed sleep loss between 2020 and 2025.