A thermometer at Heathrow Airport picked up a provisional reading of 40.2 degrees Celsius at 12:50 p.m. Tuesday, the Met Office reported, potentially breaking the previous record of 38.7 degrees Celsius set in 2019. The 12:50 p.m. record broke another record set earlier the same day of 39.1 degrees Celsius at Charlwood in Surrey, The Guardian reported.