Scorching US heat wave to hit 70 million people with third ‘heat dome’ in month

About 70 million people in the US are set to face excessive heat advisories as dangerously hot temperatures scorch much of the country’s southern and central states.The third major “heat dome” event to hit the US in the past month is gathering strength over the weekend, spanning a vast swathe of the country, from the Gulf of Mexico coast to the Great Plains and the midwest.Temperatures of 95-105F (35-40C) are expected, with some areas of the south-western US desert potentially reaching 120F (48C). The elevated heat is expected to linger into the coming week, held in place by the heat dome, which is when a high-pressure atmospheric system acts as a sort of lid, trapping heat in place over a region for days or even weeks.A man rests in the shade in Los Angeles on 20 July 2026. Photograph: Chris Torres/EPALying by the pool in Los Angeles on 20 July 2026. Photograph: Chris Torres/EPAWhile heatwaves are nothing new to American summers, the regularity and severity of such events is worsening due to the human-caused climate crisis. The release of heat-trapping gases due to the burning of fossil fuels has caused global temperatures to escalate above anything previously experienced during human civilization.It has already been a sweltering summer for many people in the US, with a huge heat dome event in early July causing some Independence Day events to be canceled in the east of the country. Another heatwave hit further west after that, causing 115F (46C) heat in Montana and temperature records to tumble.The latest heat dome event could potentially break records in the Denver area, while the National Weather Service has issued an extreme heat warning for western Nebraska, where weekend temperatures are forecast to reach 108F (42C).Heat is the deadliest weather phenomenon in the US, with elevated temperatures throughout the nighttime and high humidity in the latest heatwave set to provide no respite for people affected. Older people, pregnant people, young children and people with existing health conditions are particularly vulnerable to extreme heat.People hit the beach in Santa Monica, California, on 21 July 2026. Photograph: Chris Torres/EPADangerously hot conditions are also currently gripping much of Europe, with 250,000 people fleeing wildfires in Spain and France. A separate June heat wave resulted in an estimated 5,700 deaths in France, officials have estimated.Parts of the UK are also burning in the wake of hot, dry conditions that have primed the landscape for fire. Across the US, 88 fires are presently being tackled by firefighters.“We are experiencing exactly what the climate models in the 1990s said we should experience now,” said Andy Pershing, chief program officer at Climate Central, a climate change communications non-profit.“That is, more frequent, more severe heat waves, bigger temperature anomalies, more humidity, higher overnight temperatures. These are all part and parcel of the climate story.”The Associated Press contributed to this report