The hottest day has been recorded in the history of UK as temperatures hit 40.2°C at London Heathrow Airport on Tuesday. The previous hottest day in UK (38.7°C) was recorded in Cambridge University Botanic Garden on July 25, 2019. Many sites across UK surpassed the 2019 record today. Charlwood recorded temperatures of 39.9°C, while temperatures reached 39.6°C in Kew Gardens.