Extreme Heat

The increase in extreme heat is a direct result of a warming planet. As you can see in the animation below, even a small increase in average temperature creates a large change in our extreme temperatures. What was once considered a rare, exceptionally hot day is now becoming more common. Heat waves are getting hotter and longer and record high temperatures are outpacing record low temperatures. Since the 1980s, there have been three daily record highs for every two record lows set in the U.S.

Extreme heat has a negative impact on health and the economy, raising the risk of heat-related illnesses like heat stroke and heat exhaustion. It is also the leading cause of weather-related fatalities in the U.S. Extreme heat is associated with air stagnation, which traps pollutants and can trigger respiratory illnesses such as asthma. Extreme heat stresses crops and food supplies, worsens drought, and raises the demand for air conditioning — increasing cooling costs and straining the electric grid.

Resources for covering extreme heat:

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Interactives

More Hot Days Are Coming With Climate Change. Our Choices Will Decide How Many.

Simply enter the name of your city, town or hamlet — or any place in the Lower 48 that piques your curiosity — to see how the number of days above summer temperature thresholds will change throughout the rest of the century.

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This Is How Climate Change Will Shift the World’s Cities

Summers around the world are already warmer than they used to be, and they’re going to get dramatically hotter by century’s end if carbon pollution continues to rise. That problem will be felt most acutely in cities.

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1,001 Blistering Future Summers

Our analysis of future summers illustrates just how dramatic warming is going to be by the end of this century if current emissions trends continue unabated.

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The Hottest Cities in the U.S. vs. the Fastest Warming

This interactive map to compares the hottest places with those that are the fastest-warming.

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Is Your City Getting Dangerously Hot and Humid?

Chances are you’ve never heard the phrase “danger day” when it comes to weather. That’s because they’re rare. You’ll want to get to know it, though, because climate change is about to make them a lot more common over the next 15 years.

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Every State’s Temperature Trend for Every Season

Climate change is driving up the temperature around the year and around the globe, but topography, weather patterns and snow cover — among other factors — yield regional differences for warming.

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Climate Indicator: Extreme Heat

As global temperatures rise, the hottest temperatures and the number of areas affected by extreme heat are also on the rise

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Hot and Getting Hotter: Heat Islands Cooking U.S. Cities

Choose a city to see how much hotter urban temperatures are and explore the impacts of summer heat

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Reports

More Hot Days Are Coming with Climate Change. Our Choices Will Decide How Many.

Climate Central has developed a new tool that brings the reality of future heat to hometowns across the U.S. Includes interactive.

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How Climate Change Will Shift the World’s Cities

Billions of people call cities home, and they're going to get a lot hotter because of climate change. Includes interactive.

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Future of National Parks is Going to be a Lot Hotter

National Parks' physical boundaries might not change, but their climate boundaries will as the world warms. Includes interactive.

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The Hottest Cities in the U.S. Versus the Fastest Warming

Scorching summer temperatures are exactly what we should expect in a warming world.

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U.S. Faces Dramatic Rise in Extreme Heat, Humidity

Rising extreme heat and humidity in the U.S. cities threaten public health.

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Hot and Getting Hotter: Heat Islands Cooking U.S. Cities

Since 1970, cities have been warming, and have been getting hotter far faster than adjacent rural areas. Includes interactive.

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Warm U.S. Februaries Becoming Much More Common

The chances of seeing a February as warm as the one experienced across the Lower 48 in 2017 has increased more than threefold because of human-caused climate change.

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