UK ‘to hit 40C on regular basis even if global warming is limited to 1.5C’ Early August 2020 saw temperatures hit 34C on six consecutive days (Rick Findler/PA) British summers are likely to regularly see temperatures of above 40C even if humanity manages to limit global warming to 1.5C, the UK’s leading meteorologists have warned. The UK is already seeing increasingly extreme weather, with 2020 the third warmest, fifth wettest and eighth sunniest year on record – the first ever to fall into the top 10 for all three variables. Data published in the report The State Of The UK Climate 2020 revealed the average winter temperature for last year was 5.3C – 1.6C higher than the 1981 to 2010 average.