'Uncharted territory': Sunday was Earth's hottest day on record

Editor's note: The European Union's Copernicus Climate Change Service said on Wednesday that the record detailed in this story was surpassed on Monday, July 22.

Sunday, July 21 was Earth's hottest day on record, according to a climate tracking agency based in Europe.

The European Union's Copernicus Climate Change Service (C3S) said that based on preliminary data, July 21 was Earth's hottest day since at least 1940, with the daily global average temperature reaching 17.09℃, or about 63℉, slightly exceeding the previous record of 17.08℃ from July 6, 2023.

"While it is almost indistinguishable from the previous record, what really stands out is the difference between the temperatures since July 2023 and all previous years," the agency said on its website.

Unfortunately, Earth being hot is nothing new: Our planet has seen over 550 consecutive months with temperatures above the 20th-century average. A run of all-time temperature records, including over a year of months registering record heat, is unusual, perplexing and worrying.

Though summers are always hot, it’s important to remember that the heat events the U.S. and the world are experiencing are far beyond normal.

June was the 13th straight month of record-warm temperatures for the planet, according to data from the Copernicus Climate Change Service. That means every month for more than a year has been the warmest ever recorded. And 2023 was the hottest summer in 2,000 years, a study published last year found.

Record heat:Earth marks 12 straight months of record heat, a bewildering climate change milestone

"We are now in truly uncharted territory and as the climate keeps warming, we are bound to see new records being broken in future months and years," said C3S Director Carlo Buontempo on the agency's website.

Heat wave:Coast-to-coast high temperatures aren’t normal. When will the heat wave be over?

US weather forecast this week

According to the National Weather Service, "major to locally extreme heat risk" is expected to expand across the northern High Plains as heat gradually becomes less intense over the Central Valley of California and the Great Basin this week.

The NWS says "unsettled weather and relatively cool temperatures for July" will continue across the eastern half of the country as the ongoing heat wave over the western U.S. will gradually become less intense.

High temperatures are forecast to reach well into the 100s over the northern High Plains through Thursday with little to no rainfall expected, the NWS said in its Tuesday morning forecast.

Elsewhere, a coastal front could set off "heavy rain and thunderstorms" near the Texas coast into southwestern Louisiana on Wednesday, the NWS said, where flash flooding is possible.

Contributing: James Powel and Doyle Rice, USA TODAY

Gabe Hauari is a national trending news reporter at USA TODAY. You can follow him on X @GabeHauari or email him at Gdhauari@gannett.com.