A relentless heatwave settled over the Midwest and the East Coast, subjecting tens of millions of Americans to scorching temperatures and oppressive humidity, Reuters reported.

This extreme weather is expected to persist into the weekend, with more than 175 million people in the US under excessive heat warnings and advisories until at least Saturday afternoon, according to the National Weather Service (NWS). 

Midday heat index readings in many areas soared well above 100 degrees Fahrenheit (38 C).

To help those unable to escape the heat, major cities like Chicago, New York, and Philadelphia have opened cooling centres in public libraries and community centres. 

Recognising the dangers of extreme heat, the city of Boston declared a heat emergency and its street outreach teams will provide water to those in need. 

City officials and forecasters are urging people to avoid the hot weather, especially those who work or engage in outdoor activities, the elderly, children, and individuals with chronic illnesses. 

The NWS advises staying hydrated, seeking air-conditioned spaces, avoiding sun exposure, and checking on relatives and neighbours.

In response to the scorching temperatures, Philadelphia extended public pool and spray ground hours, while New York City released a public service announcement video on social media reminding pet owners to keep their pets well hydrated. 

During a public safety briefing, New York City Deputy Mayor Philip Banks emphasized the need to check on neighbours and loved ones.

Electric grid operators across the nation issued hot weather alerts and instructed energy companies to postpone unnecessary maintenance. Despite the extreme heat, no US grid operators have taken further drastic measures.

The increasing frequency and intensity of severe weather events are believed to be symptoms of global, human-driven climate change, according to experts. 

Heatwaves are expected to persist through August in many parts of the world.

Last month, the United States experienced its hottest June on record since 1850. 

It marked the 47th consecutive June and the 532nd consecutive month with temperatures surpassing the 20th-century average, as reported by the weather service.

Although the scorching weather is expected to subside by late Saturday, there may be chances of thunderstorms and milder temperatures into the following week, as per the weather service’s forecast.