Aug 24, 2022 - News

What extreme heat could look like in Philly in 30 years

Increase in the annual number of days with a heat index above 100°F
Caption: Note: Shaded counties are those that will, on average, have 0.5 days or more at or above a 125F° heat index in 2053; Data: First Street Foundation; Map: Axios Visuals

Think this summer's heat wave was long?

In 30 years, Philly is estimated to experience 35% more days when heat index temps tick above 90°F, climbing to 69 days — the most in the state.

  • Plus: While the city is expected to have 14 days with heat index temperatures above 100° next year, that will rise to 25 by 2053.

Driving the news: Those numbers come from a new hyperlocal analysis of current and future extreme heat events recently published by the nonprofit First Street Foundation.

  • The report examines current and future heat risks down to the property level across the country.

The big picture: In just 30 years, climate change will cause the Lower 48 states to be a far hotter and more precarious place to be during the summer, Axios Generate co-author Andrew Freedman writes.

Zoom in: All areas of Pennsylvania will continue to see temperature increases over the next three decades.

  • The cluster of counties in the southwestern part of the state will see the highest spike in days exceeding 95° in 30 years, according to the report.
  • Chester and Lancaster are the only counties in Pennsylvania expected to see heat indexes reach 125° in 30 years.

Plus: Philly will have more consecutive days with heat index temps above 90° in 2053, going from eight next year to 12.

Zoom out: The states likely to see the greatest growth in "dangerous days," with a heat index greater than 100°, are Texas, Louisiana, Arkansas, Missouri and Florida, per the analysis.

Search your risk or view by county on our interactive map


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