July was hottest month ever recorded in US as heatwaves scorched country

July was the hottest month ever recorded in the US, with repeated, scorching heatwaves across much of the country helping shatter all previous monthly temperature records stretching back over the full 132 years of reliable measurements.

Last month’s average temperature was 3.3F (1.8C) higher than the 20th century average for the contiguous United States, which excludes Alaska and Hawaii, according to new data from the National Oceanic and Atmospheric Administration (Noaa).

This means the month was the hottest July, and hottest of all months, in records that go back to 1895. It surpasses previous high marks set in July 1936, in the teeth of Dust Bowl conditions, and July 2012.

In July, the US blistered under three separate heat dome events, where soaring temperatures where held in place over a region by slow-moving high pressure weather systems. Extreme heat hit much of the US west, the Rockies, upper midwest, the Gulf of Mexico coast and south-east, according to Noaa. Wyoming recorded its hottest ever July amid temperatures a huge 5.1F above average.

Parts of the US spent the month blanketed under a haze of wildfire smoke, with large blazes engulfing forests in Canada and the US’s Pacific north-west. Scientists have made clear that the elevated heat, along with vast fires, was being significantly amplified by the human-caused climate crisis, accelerated by the burning of fossil fuels.

Heat-trapping gases released by the combustion of coal, oil and gas are driving up global temperatures and fueling deadly heatwaves that have this year roiled the US and Europe, which is having its hottest summer on record. Sprawling forest fires, resulting in the evacuations of hundreds of thousands of people and the inhalation of toxic smoke for millions more, have become a feature of the season in North America and Europe.

The average monthly heat record set in July – although the record for maximum daily temperatures remains July 2024 – has taken a toll on the lives of many Americans, polling released by AP-NORC last week showed.

Nearly half of people in the US said the impact on their electricity bills, which have risen even as people have sought to cool themselves with air conditioning, has been “major”. Meanwhile, about 40% of people said the heat had altered their travel plans.

About two-thirds of people polled reported having their families’ outdoor activities affected by the extreme heat, while about half said their exercise routine had been hampered. The impacts across various areas of Americans’ lives are more widespread than when the same questions were asked two years ago, the polling found.

Despite the unfolding consequences of the climate crisis, Donald Trump has continued his attempts to axe cheap clean energy and bolster the production of fossil fuels. The US president has called climate science “bullshit” and a “con job” in the past and has sought to encourage other countries to also burn more of the fossil fuels that are driving up temperatures beyond those which humans have ever lived in before.

An unusually strong El Niño event, a periodic climate feature where a section of the Pacific Ocean heats up causing weather around the world to alter, is likely to cause next year to be the hottest on record globally, surpassing a record set just in 2024. Some scientists think the developing El Niño could even ensure that this year is the one that breaks the record.

“The bottom line, though, is that we expect to set record global temperatures as long as carbon emissions continue to warm the planet, and typically these records are set during major El Niño events,” said Michael Mann, a climate scientist at the University of Pennsylvania.