Where Will Extreme Heat Hit Hardest by 2050?

Explore How Climate and Population Changes Intensify Heat Risks in U.S. Cities

Extreme heat exposure from climate change will impact health based on how often and how intensely heat occurs—and how vulnerable local populations are. To understand where future heat will hit hardest, we analyzed projections from over 30 climate models and used the median scenario. Explore the visualizations below and more here, and embed on your own site! Please contact Zach Popp (zpopp@bu.edu) with any questions or comments.

Use the tool below to explore how heat index days (which reflect both temperature and humidity) are expected to rise in any of the 100 largest U.S. cities by 2050. We show projections across three “shared socioeconomic pathways”—scenarios of global development and emissions. SSP585 reflects the most severe outcome, with the highest projected emissions.

In addition to the number of hot days we also estimate the 95th percentile temperature. This represents the high temperature for approximately the twentieth hottest day of the year.

Where are the counties where the biggest increases are expected to happen?

See hot the increase in extreme heat days differs across the US in the near future. The change in the average number of hot days across 20-year periods are shown to demonstrate long-term trends not driven by single hot or cold years.

Changes in hot days are concentrated in the areas of the US that are the hottest today, like the US South and states like Texas and Florida. When we look at the high temperature on the hottest days (the 95th percentile), we see that areas that are cooler today in the Northeast and Midwest see the fastest rate of change. The rate of increase in areas that face less heat extremes today can stress aging infrastructure and pose unique health hazards.