<Tr> <Th> Areas affected </Th> <Td_colspan="2"> United Kingdom </Td> </Tr> <Tr> <Th> Highest temperature </Th> <Td_colspan="2"> 34.5 ° C (94.1 ° F) at London Heathrow </Td> </Tr> <P> The 2017 United Kingdom heat wave was an event that took place in the United Kingdom in June 2017 . Temperatures at Heathrow Airport reached a decades - high of 34.5 ° C (94.1 ° F), the hottest June temperature since 1976, on 21 June . This marked five consecutive days of temperatures above 30 ° C (86 ° F), making it an official heatwave, and the first June heatwave since 1995 . </P> <P> An incoming cold front from 21 June led to some rainfall and predictions of thunderstorms, similar to those seen earlier in the year, because it would clash with the heat . A yellow storm warning was issued for the North of England and Wales, and South of Scotland, for 27 hours from 0300 on 21 June . Another yellow warning was given nationwide the following day from the time at which the previous warning ends until 1300 (1pm). The Met Office also warned of risks of localised flooding, large hail, and severe thunderstorms ranging from the Midlands northwards from the afternoon of 21 June, though official weather warnings showed that the worst of the storm will have travelled to the South East and East Coast by mid-morning on 22 June . </P>

What was the hottest day in the uk 2017