From the Met Office in September last year,
"The UK as a whole has had its ninth hottest summer on record, with an average of 15.28°C. This is the hottest summer for the UK since 2018. While 2019 and 2020 both experienced extreme heatwave events, in contrast 2021 temperatures reached a peak of 32.2°C at Heathrow on 20th July. However, relatively high temperatures in June and July, coupled with persistently high minimum temperatures and relative warmth across the north of the UK have pushed this year up the rankings."