Philadelphia 250

Dangerous heat and a few thunderstorms are possible around Philadelphia on the Fourth of July

Feels-like temperatures could reach as high as 110 degrees Wednesday through Friday. Storms could dampen July Fourth fireworks shows.

Cory Sharber

June 29, 2026

Residents of Reese Street in the Hunting Park Section of Philadelphia opened a fire hydrant during an intense heat wave on July 20, 2022. (Kimberly Paynter/WHYY)

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As Philadelphia closes in on what could be its busiest weekend in history with a packed schedule of celebrations of America’s semiquincentennial and a Fourth of July World Cup match, meteorologists are warning of an extended period of extreme and dangerous heat for much of the week.

Temperatures exceeding 95 degrees are almost all but guaranteed from Wednesday through Friday in the Philadelphia area, according to Michael Silva, a lead meteorologist at the National Weather Service in Mount Holly.

While the city has not officially issued a “Code Red” yet, the heat health emergency goes into effect when heat indices are forecast to exceed 95 degrees for three consecutive days.

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Silva said a high-pressure system settling over the central United States is to blame for the temperatures, bringing hot and humid air into the region.

The high humidity will push heat indices, or “feels-like” temperatures, closer to 110 degrees, he said.

While heat is the main concern this week, some afternoon thunderstorms are possible Saturday, which could impact some Fourth of July fireworks shows.

“I would say the best timing would be late afternoon into the evening, which would be typical for a summertime pattern like this where we have a hot, humid air mass,” Silva said. “Because it’s so hot and humid, you have all that energy for thunderstorms to develop.”

The National Weather Service suggests people limit their outdoor plans during the extreme heat, stay hydrated and stay in an air-conditioned environment.

On July 4, Philadelphia will be celebrating Independence Day with massive events lined up for the occasion, including the One Philly: Unity Concert for America on the Benjamin Franklin Parkway, the Salute to Independence Semiquincentennial Parade starting at Independence Hall, as well as a FIFA World Cup Round of 16 match in South Philadelphia.

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