Science Alert warned Monday “worsening human-induced climate change” is contributing to an increase in heat-related deaths as the United States languishes under a “heat dome.”

“Despite being preventable, the leading weather-related deaths in the US are caused by heat,” the article states, adding that heat-related deaths “are rising as heat waves like this one occur more regularly thanks to worsening human-induced climate change.”

At least 550 pilgrims have died during the hajj, underscoring the gruelling nature of the pilgrimage which again unfolded in scorching temperatures this year.

At least 323 of those who died were Egyptians, most of them succumbing to heat-related illnesses, the two Arab diplomats coordinating their countries’ responses told AFP.

The atmospheric heat dome that is causing record temperatures in parts of the Northeast arrived earlier than usual, is situated farther north and is the strongest in several decades, according to weather experts.

Heat domes usually form in the South and Southwest during the summer and are rarely seen in the Northeast in mid-June. 

“It is out of the ordinary and is unusual to see this type of intense high,” said Paul Pastelok, senior meteorologist at AccuWeather. 

Dozens of environmental, labor and health care groups banded together on Monday to file a petition to push the Federal Emergency Management Agency to declare extreme heat and wildfire smoke as “major disasters,” like floods and tornadoes.

The petition is a major push to get the federal government to help states and local communities that are straining under the growing costs of climate change.

A record-breaking heat wave with a combination of humidity and temperatures well into the 90s was descending on cities in the Midwest and heading to the Northeast this week in what is expected to be a dangerous weather system days before summer officially begins, forecasters said.

“The duration of this heat wave is notable and potentially the longest experienced in decades for some locations,” the National Weather Service said on social media on Sunday.

A high-pressure weather system could bring record-breaking temperatures to central and eastern parts of the United States this week, National Weather Service forecasters said on Monday, threatening a large swath of the country with multi-day excessive heat.

Some 80 million people are currently under a heat advisory or warning as heat is expected to surpass 90 degrees Fahrenheit (32.2 degrees Celsius) and flirt with 100 degrees in some areas, which is 20 degrees above average this time of year, meteorologist Andrew Orrison of the National Weather Service said.

Tens of millions of people from the Ohio Valley to the Northeast are about to experience the first significant heat wave of the summer, and it has the potential to be not only record-breaking but also life-threatening.

The sweltering temperatures are the result of a massive ridge of high pressure that’s establishing itself over the eastern U.S., and temperatures are set to skyrocket into the 90s and approach the 100-degree mark in many cities. The humidity will make it feel even hotter, with feels-like temperatures soaring above 100 degrees.

A prolonged and deadly heat wave in Mexico, one of the most extreme the country has faced, shows little sign of easing and is oozing into the United States, where it has already set records and fueled violent storms.

The heat has been breaking records in Mexico since early May. Many Mexican states have observed their highest temperatures on record, while more than 80 percent of the country is also enduring drought. Mexico City has set all-time record highs on multiple occasions, while fears grow that it may run out of water.

Mexico has been consuming record amounts of electricity and occasionally more than its utility infrastructure can generate and transmit, official data showed, as scorching heat raises the likelihood of power outages.

In the late afternoon on Monday, Mexico consumed 51,595 megawatts of electricity across the country, grid operator CENACE recorded.

When demand exceeds supply, the country becomes much more prone to outages.

The extreme heatwave in Mexico is not only affecting the environment, it's wreaking havoc on the howler monkeys and causing them to fall dead out of trees, the Associated Press reported. 

"They were falling out of the trees like apples. They were in a state of severe dehydration, and they died within a matter of minutes," wildlife biologist Gilberto Pozo described what he witnessed to the AP.