A historic heatwave is sweeping across the United States, with record-breaking temperatures spreading from the Midwest to the eastern US on Wednesday, July 1, 2026. Tens of millions of Americans are under heat warnings expected to persist through the July 4 holiday weekend, when the nation celebrates its 250th anniversary.
Extreme Heat and Real-Feel Temperatures
The extreme heat is forecast to push real-feel temperatures to between 100 and 115 degrees Fahrenheit (37.8 to 46.1 degrees Celsius) across much of the affected region. This increases the risk of heat-related illnesses for vulnerable populations and threatens to overwhelm power grids already strained by rising consumption from data centers and electric vehicles.
In Hill City, Kansas, a small high plains town about 270 miles east of Denver, mail carrier Sabrina Hooper, 34, is struggling with temperatures exceeding 100 degrees just one week after starting her job. "It's completely debilitating," Hooper said, describing the heat's effect on her work, which involves walking up to 10 miles daily to deliver parcels. She finds some relief from lawn sprinklers: "It's so nice. You can take your hat off, get it wet, slap it back on your head." Hill City was the nation's hottest spot for five consecutive days in 2012, during another record-breaking heatwave that pushed the town's heat index to 108 degrees. The heat index measures how it feels when humidity is factored into air temperature.
Struggles in Texas and Chicago
Dana Robles, a resident of Brownsville, Texas, located just off the Gulf Coast at the US-Mexico border, expressed concern on Wednesday about the rising costs of cooling her home as the heat index reached 108 degrees. During peak temperatures, her family's monthly power bill can exceed $300, nearly one-third of their rent. Robles also fears blackouts due to the overtaxed power grid. "I'm scared the electricity is going to go off all day and our food is going to get spoiled," she said.
In Chicago, high-school science teacher Michelle Klein, 57, began preparing for the heat over the weekend. She filled her car with gas, did her weekly grocery shopping early, stocked the refrigerator with extra cold drinks, and gave her plants a deep soak. "The basil was being a diva and needed another drink of water this morning," Klein said on Tuesday evening after going on her usual evening walk despite a heat index of 103 degrees.
In the Chicago suburbs, property investor Amy Kaspar, 50, received an urgent call Monday night from a tenant whose air conditioner was only blowing warm air. Kaspar discovered the appliance was working fine but could not keep up with cooling the unit due to the intense heat and humidity. "Combined with the wind, it feels like standing behind the exhaust of a bus right now in Chicago," Kaspar said.
Cooling Centers and Community Support
Chicago's Office of Emergency Management and Communications urged residents on Wednesday to periodically check in with relatives, neighbors, seniors, and other vulnerable populations. If contact cannot be made, residents can request a well-being check from the city by calling 311.
The scorching US temperatures mirror those in western Europe, which recently experienced its own record-breaking heatwave, an event scientists said would have been "virtually impossible" without human-caused climate change. Studies have confirmed that greenhouse gas emissions are making heatwaves around the world more likely and intense.
New York City Takes Action
The extreme heat began creeping into New York City on Wednesday morning. The city has opened hundreds of cooling centers and deployed more than a dozen "cool vans" equipped with water, electrolytes, sunscreen, and meals for New Yorkers in need, according to Mayor Zohran Mamdani at a press conference.
At a senior center in Harlem, air conditioning was on full blast, and a sign in 13 languages advertised the space as a cooling center. Director Richard Allman said it would remain open beyond usual hours over the July 4 weekend. "We try to make this a comfortable place for people on an extra-hot day," he said.
Ahead of the heatwave, city leaders asked operators of signs in Times Square to reduce billboard brightness to lower energy consumption and requested businesses set thermostats no lower than 78 degrees. The city's energy provider, Con Edison, urged customers to limit energy use from 2 p.m. to 10 p.m. The city has also extended public pool hours, opened additional cooling centers in libraries and municipal buildings, and expanded street outreach efforts.
