Brutal US heat dome threatens July 4th, World Cup weekend; 100°F in New York City

Published 3 July 2026 · us

A searing heat dome will push electricity demand across the eastern US toward record levels over the July 4 holiday, testing power grids as air

A searing heat dome will push electricity demand across the eastern US toward record levels over the July 4 holiday, testing power grids as air conditioners run full tilt on a busy World Cup weekend. The dangerous heat wave is forecast to bring triple-digit temperatures to many US cities, including New York. More than 180 million people spanning Kansas to Maine were under extreme heat warnings or heat advisories on Friday, according to the US Weather Prediction Center. Heat advisories stretch from Michigan as far south as Alabama. “Today looks to be quite oppressive,” Frank Pereira said by telephone, with “well-above-normal temperatures from the Plains and Midwest to the Mid-Atlantic and Northeast.” Also Read | US Independence Day 2026: Check July 4 store hours and status Hundreds of temperature records — for daytime highs and warm overnight lows — are likely to be tested through the weekend, according to the US Weather Prediction Center.

That’s straining power systems across the region, with more than 71,000 customers without electricity just before 8:30 a.m. New York time, data from PowerOutage.com show. The country’s largest grid serving nearly a fifth of Americans from Washington to Chicago is operating in an emergency — at the lowest of three levels — for the third consecutive day. PJM Interconnection LLC ordered all power plants to be available at maximum levels for the entire day as it faces a capacity emergency. “PJM is not in an emergency for any other reasons really than power outages,” said Adam Sinn, chief executive officer of hedge fund Aspire Commodities. There were about 9.5 gigawatts of generation outages in the mid-Atlantic region, including data centers concentrated in northern Virginia, compared to prior forecasts that had shown less than a third of that, he said. While electricity usage is set to ease slightly Friday amid holiday travel, cooling demand may spike again as the hot and humid conditions persist.

The risk of failures at power plants or other critical equipment rises with high sustained demand. The sprawling heat dome adds another major complication: grids that typically rely on each other for spare supplies may limit supplies to neighbors to keep their systems stable. Temperatures in Central Park spiked to 100F (38C) on Thursday — making it the hottest day in the city since 2012. Records were set from Caribou, Maine to Chattanooga, Tennessee, including in Boston, Baltimore’s Inner Harbor, and Washington’s Reagan Airport, Pereira said. Oppressive temperatures and humidity are forecast across the city and the eastern half of the US through the weekend. Consolidated Edison Co., which runs New York City’s electric utility, has asked about 133,000 customers in Northern Brooklyn to conserve energy to allow crew to repair equipment. Voltage was throttled back by 8% to allow them to do it safely, limiting power flows. Those households were asked to not use washers, dryers and microwaves, and to use only one air conditioner if they have two, the utility said in a statement.