NEW YORK • A massive heatwave that has enveloped the US Midwest pushed into the north-east on Friday, ushering in temperatures that could top 38 deg C in Washington and prompting utilities to take steps to prevent power outages.
The huge blob of warm air is likely to blanket the region, home to one-third of the US population, through today with little overnight relief, said meteorologist David Roth of the National Weather Service's Weather Prediction Centre.
He said: "There are 124 million people under a heat advisory or excessive heat warning."
As of Friday, the heatwave sprawled from Kansas to the Atlantic Coast, and from South Caro-lina north to Maine. It was expected to intensify over the weekend.
Utilities in the eastern half of the United States expect to have enough resources to meet power demand on Friday but asked people to turn down air-conditioners to avoid putting stress on the system, which could cause outages.
On July 13, parts of Manhattan lost power for hours, darkening Broadway theatres, halting subways and closing restaurants and shops in a partial blackout blamed on a faulty piece of equipment.
Early on Friday, as the heat intensified in downtown Madison, Wisconsin, 11,600 homes and businesses lost power after fires erupted at two substations near the state capitol.
With temperatures forecast to hit 34 deg C later in the day, governor Tony Evers asked non-essential state workers to stay home.
By mid-afternoon, power had been restored to all but about 3,500 customers, according to Madison Gas and Electric.
On the East Coast, temperatures on Friday were forecast to reach near 38 deg C in Washington, 36 deg C in Philadelphia and 33 deg C in New York, where it would feel more like 43 deg C with high humidity, said Mr Roth.
Yesterday, the forecast called for 37 deg C in New York and Philadelphia and 38 deg C in Washington. Much the same was in the forecast for today.
Said Mr Fonik Bitaly, 28, who was entering his sixth hour of work dressed as a costumed character, Batman, in New York City's Times Square: "It's really, really hard to be outside right now."
The dangers posed by extreme heat and humidity prompted officials to scrap outdoor competitions, including yesterday's horse races at Saratoga Race Course in upstate New York and today's New York City Triathlon.
"As soon as you get outside, it's like 'Boom!' said Mr Loig Loury, 32, who moved to New York from Paris last year. "The heat attacks you."
To keep cool during past heatwaves, suburban children typically ran under lawn sprinklers and those in the city frolicked in the spray of fire hydrants, but the New York City Fire Department (FDNY) warned that to avoid creating a hazard, special spray caps handed out by firehouses should be used.
"If you open a fire hydrant without these caps, you endanger your neighbours because the water pressure drops and our firefighters are not able to fight fires," FDNY Commissioner Daniel Nigro wrote on social media.