News

Summer’s not just hot: humidity has increased

Philly’s feeling the heat during recent waves, and it’s not just the temperature that’s gone up.

Philadelphia has had a hot summer.

By early August, there were 27 times that the temperature reached 90 or above in Philadelphia. A normal average is 30 for the entire year.

Climate change continues to bring hotter and wetter weather, but another consequence isn’t discussed as frequently: an increase in humidity.

Summer equivalent temperatures have increased three times than summer air temps since 1950, according to Climate Central.

This is dangerous because the combination of high heat and humidity can compromise our body’s ability to cool itself through sweating. Higher humidity levels limit evaporative cooling, which can lead to heat stress and illness.

Although the US North Central and Midwest regions have seen relatively modest increases in summer temps, there’s been a big increase in humidity.

Those at greatest health risks are vulnerable populations like children, older adults, athletes, outdoor workers, and communities of color.

How to stay cool during high heat

The City of Philadelphia opens cooling centers during extreme heat and humidity. You can find a cooling center on the City’s website.

Chart from CDC
Julie Hancher

Julie Hancher is Editor-in-Chief of Green Philly, sharing her expertise of all things sustainable in the city of brotherly love. She enjoys long walks in the park with local beer and greening her travels, cooking & cat, Sir Floofus Drake.

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