01-07-2025
June heat dome follows worrying climate trend
Summer in Britain is typically blessed with a mild Goldilocks climate, not too hot and not too cold. As the historian William Camden wrote in 1586 in his book Britannia: 'The aire so kinde and temperate that not only the Summers be not excessive hot by reason of continual gentle winds that abate their heat.'
So it has been something of a surprise for two heatwaves to scorch the country in quick succession this June, typically the mildest month of summer. The first heatwave around the time of the summer solstice on June 21 saw temperatures reach 33.2C, and this weekend was again hot and humid for many parts, reaching highs of over 30C. And on Monday temperatures are likely to peak at 33C or more in parts of southeast England, although staying notably cooler in Scotland.
The hot and humid air has drifted up from a brutal heatwave in Europe. On Saturday, El Granado in southwest Spain hit 45.8C, a new Spanish record for June, whilst France reached a high of 41.3C — normally temperatures this high are expected in July or August. And the heat was widespread through the western Mediterranean with Spain, Portugal, France and Italy all under health and wildfire warnings from the searing temperatures.
This heatwave has been cooked up under a heat dome, a large block of high pressure sat in place over much of Europe for some considerable time, trapping heat under scorching hot sunshine. And like some sort of giant pressure cooker in the atmosphere, that heat has built up day by day into unbearably high temperatures.
Heatwaves in June have happened before even in the UK, most memorably in the hot summer of 1976, but the heat then was not widespread across Europe and elsewhere in the world. The current heat also follows an alarming pattern of blistering hot summers over recent years, a change driven by greenhouse gases that continue to grow more excessive every year. But then the warming climate was predicted long ago — it's only the pace of change that has come as a shock and does not bode well for the future.
