A brutal heat wave threatened July 4 celebrations, World Cup matches and power grids across the eastern United States on Friday as near-record temperatures blanketed the region.
About 160 million Americans were under major or extreme heat warnings as the nation prepared to celebrate the 250th anniversary of its independence, according to the National Weather Service.
Extreme temperatures forced organizers to postpone part of the Independence Day festivities on the National Mall, the sprawling park that stretches from the U.S. Capitol to the Washington Monument.
The heat also took an early toll on revelers. A young woman who appeared to be suffering from heat exhaustion was treated by paramedics and evacuated from the Great American State Fair on the National Mall.
"It's like the 30th person," said an event staffer. "They might have to shut this event down."
Less than 90 minutes later, organizers did just that.
The annual Independence Day Parade in Washington, set for Saturday morning, was also canceled because of extreme heat, organizers said.
In New York City, the heat index, the apparent temperature when humidity is factored in, stood at 41 degrees Celsius (105 degrees Fahrenheit) in midafternoon, shy of the 46 degrees Celsius (115 degrees Fahrenheit) forecasters had predicted.
Still, the brutal heat prompted a massive government response, with cooling centers opening across the city and public swimming pools extending their hours.
Across the country, "numerous daily temperature records are expected today and Independence Day, with some consecutive-day, monthly, and all-time records possible," the National Weather Service said.
Early on Friday, Hang Dang, a 76-year-old retiree, said she was not letting the extreme temperatures keep her from attending July 4 celebrations in Washington.
"I came to the U.S. in 1975 from Vietnam and ... I was here for the bicentennial," Dang told Agence France-Presse (AFP), noting that she drove 12 hours from Florida to attend the festivities.
"I said I've got to get back for the 250th because I don't think I'll make it to the 300th!" she joked as a Marine Corps Osprey aircraft hovered nearby.
Around midday, lines to enter the state fair appeared to stretch more than 400 feet (120 meters) as temperatures climbed toward a forecast high of 39 degrees Celsius (102 degrees Fahrenheit).
Inside the festival, attendees sought shelter in the short midday shadows cast by temporary buildings set up for the event.
Standing outside one pavilion, a woman repeatedly shouted, "Homeland Security, here! Spin the wheel, win a prize! Full blast A/C in there!" as she pointed to the door.
About an hour later, a voice over the public address system announced: "Attention, fairgoers, the event has been postponed. We will reopen at 5 p.m. Please proceed to the nearest exit."
In Miami, a city no stranger to heat, Argentina and Cape Verde faced off in a stadium with a partial roof canopy but no air conditioning. The forecast heat index for the 6 p.m. kickoff was 38 degrees Celsius (100 degrees Fahrenheit).
On Saturday, France and Paraguay will clash in Philadelphia, where the heat index could reach 41 degrees Celsius (105 degrees Fahrenheit).
Because of the heat, FIFA has introduced a mandatory hydration break in each half of every game at this World Cup, although it was unclear whether that would be adequate for matches played outdoors during the heat wave.
Preliminary data showed the daily heat record in the U.S. capital was likely broken when the nearby airport reached 39 degrees Celsius (102 degrees Fahrenheit), topping the previous July 4 record of 38 degrees Celsius (101 degrees Fahrenheit), set in 1966.
The intense heat and heavy air conditioner use were stressing electricity grids across the country.
New York utility provider Con Edison said its crews restored electricity to about 60,000 customers after heat wave-driven outages.
More than 22,000 customers were without power around 4:30 p.m. (8:00 p.m. GMT) Friday across New York City and some surrounding suburbs.
PJM, the company that coordinates multiple power grids across the East Coast and parts of the Midwest serving 67 million customers, said data centers were prepared to switch to emergency backup power Thursday to ease strain on the grid, among other measures.
Although that step was not taken, the company said it remained an option for Friday.
