Record-breaking heat wave threatens July 4 celebrations and World Cup matches as US cities open cooling centers

Heat dome delivers triple-digit temperatures

A sprawling heat dome has settled over the central and eastern United States, pushing temperatures toward 100°F (38°C) and higher. By Thursday, New York City is forecast to hit 100°F for the first time since 2012, while Washington D.C. may endure three consecutive days at or above that mark. Philadelphia could tie its record of three straight 100-degree days, set in 1966 and 1993. The National Weather Service warns that heat indices, combining temperature and humidity, will climb to 115°F in some areas.

By the numbers: 73 million Americans are expected to experience triple‑digit heat through Sunday, 190 million will face extreme humidity, and 205 million will be at major or extreme heat risk through Monday, according to NOAA’s HeatRisk scale.

This is Texas hot, which we don't usually see here, so it's serious.

Widespread records and overnight risks

Meteorologists expect more than 100 daily high‑temperature records to be broken from Tennessee to Maine, along with over 200 record‑high minimums, nights where the temperature never drops to comfortable levels. These warm overnight lows are especially dangerous because the body loses its chance to recover.

When we have overnight temperatures that don't drop below 75 degrees, you start to see some pretty extraordinary outcomes with respect to heat illness and heat stroke, and even mortality.

Cities scramble to protect residents

New York Mayor Zohran Mamdani signed an executive order aimed at protecting the city’s estimated 93,000 outdoor workers and declared an emergency heat plan. Libraries, senior centers, and other air‑conditioned public buildings have been designated as cooling centers. The city is also deploying misting fans and hydration vans in areas where street vendors and delivery workers gather. Chicago has opened its own cooling centers and is conducting wellness checks on vulnerable populations.

We are possibly facing the second hottest day in New York City history in more than a decade. This is life‑threatening heat.

Heat casts shadow over July 4 and World Cup

The heat wave peaks just as the nation marks its 250th Independence Day with outdoor festivities, including what organizers call the largest fireworks display in history on the National Mall in Washington. Meanwhile, the 2026 World Cup, co‑hosted by the U.S., Canada, and Mexico, is seeing knockout‑stage matches played under oppressive conditions. France and Sweden’s match at New York New Jersey Stadium and Sunday’s Brazil‑Norway contest in East Rutherford, where temperatures could reach 34°C (93°F), are among the fixtures affected. Earlier, two group‑stage games exceeded the temperature threshold at which the global players’ union recommends postponement, and dozens of fans were treated for heat illness in Houston and Miami.

Health officials urge caution

Authorities stress that heat is the deadliest weather phenomenon, killing more people annually than hurricanes or tornadoes. Nine children have already died in hot cars this year in the U.S., officials note, and they advise keeping pets indoors and off hot asphalt. A rapid‑attribution study by World Weather Attribution found that a similar heat wave in Europe last week would not have been possible without climate change.

Heat is sneaky. You hear lightning, you know to go indoors. You know to escape hurricanes and tornadoes. But heat is the No. 1 weather‑related killer.