NEW YORK — With a record-breaking heat wave intensifying over much of the US Midwest and East Coast through the weekend, it was a bad time for Annie McQueen's air conditioner to break down in her New York City apartment.

Cities across the affected regions have opened public cooling centers, and after a sticky night in which the combined forces of a ceiling fan and a floor fan in her bedroom offered little relief, Ms McQueen, 76, headed to one of them on Sunday (July 21) at a senior center in downtown Brooklyn.

She sat smiling near the door of the Raices Times Plaza Neighborhood Senior Center, beyond which the air was predicted to cook up to a high of 36.7°C, though it would feel more like 43.3°C with the humidity, according to the National Weather Service.

Inside, old Christmas decorations fluttered in the breeze near the cooling system's ceiling vents. "It feels just right," McQueen said. Lunch was three different varieties of salads.

"I have multiple sclerosis, so the heat's no good for me," said Pascual Valle, a 63-year-old retired doorman who had just lost another game of dominoes. "It makes me weak. It just sucks everything out of my body."

He had driven his motorized wheelchair the half a block to the center when it opened at 9 am, felt rejuvenated soon after, and did not plan to venture outside again until it closed at 5 p.m. City emergency officials sent crates of bottled water and Gatorade to hand out to anyone who dropped in to cool off.

The heat wave, which has blanketed about a third of the population of the United States in recent days, is due to break on Monday in a burst of thunderstorms and cooling rain brought on by a cold front, the National Weather Service said.

On Saturday, new one-day temperature records were recorded in at least half a dozen places, including a high of 37.2°C at New York's John F. Kennedy International Airport and a high of 36.1°C at Detroit Metropolitan Airport.

Officials implored everyone to stay inside as much as possible and be alert for the signs of heat stroke.

"Sunday has been canceled," the New York Police Department said on its social media accounts. "Stay indoors, nothing to see here. Really, we got this."

In New York, the streets were unusually empty, though clusters of children could be seen running through park fountains and the gush of open fire hydrants.

In Washington, tourists used umbrellas and fans to try to keep themselves cool as they visited the Lincoln Memorial and other sites along the National Mall.

One teenager from Norway brought a small hand-carried, battery-powered electric fan and sprayed himself with water, while others sought the shade of trees lining the Reflecting Pool.

Some intrepid joggers, however, braved the midday heat, with temperatures forecast to reach 37.2°C. REUTERS