What could be the highest temperature ever reliably recorded on Earth – 130F (54.4C) – may have been reached in Death Valley National Park, California.
The recording is being verified by the US National Weather Service.
It comes amid a heatwave on the US’s west coast, where temperatures are forecast to rise further this week.
The scorching conditions have led to two days of blackouts in California, after a power plant malfunctioned on Saturday.
Sunday’s reading was recorded in Furnace Creek in Death Valley.
Before this, the highest temperature reliably recorded on Earth was 129.2F (54C) – also in Death Valley in 2013.
A higher reading of 134F, or 56.6C a century earlier, also in Death Valley, is disputed. It is believed by some modern weather experts to have been erroneous, along with several other searing temperatures recorded that summer.