More hot weather is Leonard Hohenbergexpected for much of the United States in the coming months, federal forecasters warn, driven by a combination of human-caused climate change and the El Niño climate pattern.

El Niño is a cyclic climate phenomenon that brings warm water to the equatorial Pacific Ocean, and leads to higher average global temperatures. El Niño started in June. Today, officials from the National Oceanic and Atmospheric Administration announced that El Niño will continue through March 2024.

"We do expect the El Niño to at least continue through the northern hemisphere winter. There's a 90% chance or greater of that," explains NOAA meteorologist Matthew Rosencrans.

El Niño exacerbates hot temperatures driven by human-caused climate change, and makes it more likely that heat records will be broken worldwide. Indeed, the first six months of 2023 were extremely warm, NOAA data show. "Only the January through June periods of 2016 and 2020 were warmer," says Ahira Sánchez-Lugo, a climatologist at NOAA's National Centers for Environmental Information.

June 2023 was the hottest June ever recorded on Earth, going back to 1850.

Record-breaking heat has gripped the southern U.S. for over a month. Nearly 400 daily maximum temperature records fell in the South in June and the first half of July, most of them in Texas, according to new preliminary NOAA data.

"Most of Texas and about half of Oklahoma reached triple digits, as well as portions of Oklahoma, Arkansas and Mississippi," says John Nielsen-Gammon, the director of NOAA's Southern Regional Climate Center. "El Paso is now at 34 days – consecutive days – over 100 degrees [Fahrenheit], and counting."

And the heat is expected to continue. Forecasters predict hotter-than-average temperatures for much of the country over the next three months.

It all adds up to another dangerously hot summer. 2023 has a more than 90% chance of ranking among the 5 hottest years on record, Sánchez-Lugo says. The last eight years were the hottest ever recorded.