The hottest temperature ever recorded on Earth may have been hit on Sunday after Death Valley in California sweltered in 54.4C (130F) heat.
The National Weather Service tweeted the potentially record-breaking temperature and said it beat Death Valley's previous August record.
An analysis of the record in 2016 found that it was 'essentially not possible from a meteorological perspective'.
A 55C (131F) reading from Kebili in Tunisia from 7 July 1931 also has 'serious credibility issues', according to the same study's author.
But according to Randy Cerveny, who leads the World Meteorological Organisation's weather and climate extremes team, the temperature recorded on Sunday seemed to be 'legitimate'.
The weather service warned of 'blistering, widespread excessive heat across the West', while staff at the park told visitors: "Drink plenty of water and carry extra. Avoid hiking (after 10am). Travel prepared to survive."
Death Valley has the current record for the hottest temperature recorded on Earth, an incredible 56.6C 134F degree was recorded on 10 July 1913, however, experts have cast doubt on the accuracy of that reading.
