Over 80m people under air quality alerts as extreme heat and smoke spreads across US – live

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A Florida man and his teenage stepson died on Monday after hiking in extreme heat at Big Bend national park in south-west Texas, according to officials.

The boy died after falling ill during the hike, and his stepfather was killed in a car accident as he tried to find help, authorities said. Their identities weren’t immediately released.

The stepfather, 31, had been hiking the Marufo Vega Trail on Friday with his two stepsons, ages 14 and 21.

Temperatures at the time were 119F (48C), the National Park Service said. Like other parts of Texas, the park was experiencing extreme heat with daily high temperatures ranging from 110F (43C) to 119F.

Read the full story here.

Big Bend National Park in Texas Photograph: Inge Johnsson/Alamy

Reports are surfacing from Texas about inmates “being cooked alive” in state jails as the state struggles with a record-breaking heatwave.

Several emails sent from inmates and reviewed by Nexstar reveal inmates grappling with the heat and a lack of hydration.

“I’m having a really hard time breathing right now… It’s so humid you can’t breath… we were in AC for shakedown yesterday all morning and when we came back it was 118 degrees in here and going from AC to that made me sick to the point I threw up my electrolyte drink and I just felt sick and nauseous all day… not sure how long ima last here in the heat,” one inmate wrote.

Another person wrote, “We are still not getting water… They don’t give us respite at all. It’s very hot, we only have one big fan. They don’t give us respite showers AT ALL.”

KXAN reports that out of the 100 units operated by the Texas Department of Criminal Justice, 14 do not have air conditioning. Meanwhile, 55 units have “partial” AC that is available in “respite areas” such as cooled chapels but not in individual cell blocks.

Heat and smoke bring suffering for almost 100m Americans as climate crisis bites

Good morning.

Extreme waves of heat and smoke spreading across the US have placed over 80 million Americans under air quality alerts.

With smoke from Canada’s wildfires continuing to drift into the US, Chicago and Detroit saw thick shrouds of smoke on Tuesday evening and for several hours, both cities had the worst air qualities in the world, according to IQAir.

Meanwhile, the record-breaking heatwave expanding across southern states was made five times more likely by the climate crisis, according to scientists. In Texas, temperatures have reached triple digits as a record heatwave in the south entered its third week. According to meteorologists, major portions of Texas are forecast to be hotter than 99% of the world on Wednesday, with the heat index value predicted to be as high as 115F, or 46C.

With the country facing extreme temperatures, the North American Energy Reliability Corporation has predicted that two-thirds of North America is “at risk of energy shortfalls this summer during periods of extreme demand”.

Stay tuned as we bring you the latest updates from across the country.