Plume of hot air makes for a sticky situation
It is rare for the Met Office to issue an amber heat warning, but today sees one coming into force for the next three days for much of England and Wales on account of extreme high temperatures, by day and by night. Monday and Tuesday are predicted to see 37C (98.6F) in south eastern England as a plume of hot air blows in on a southerly breeze from France and Spain, where it has brought temperatures of 47C (116.6F) to the city of Seville.
After a few days’ lull in the very hot conditions of the previous week, yesterday the heat started to build as the wind direction switched from a cooling northerly to a sticky southerly. And this morning will begin as it intends to go on with sunshine and hardly a drop of rain, save perhaps for the far north of Scotland. It is the parts closest to the continent that will see the highest temperatures – 32C (90F) in London – but this warmth will spread to most parts, with 31C (88F) in the English Midlands, 30C (86F) in South Wales and along the eastern seaboard, and 28C (82F) in Liverpool. All are within the area covered by the amber warning. Just outside are Cornwall at 25C (77F), and Glasgow, Edinburgh and Belfast at 24C (75F).
But that warm breeze keeps coming as the working week arrives, pushing the mercury higher still. That southeastern corner could see 37C (98.6F), with some forecasts suggesting that the 38.7C (101.7F) recorded in 2019 in Cambridge as our hottest ever day potentially under threat. Night-time temperatures will remain stubbornly high, too, making sleep difficult.
Relief will come as Tuesday turns into Wednesday, with low pressure heading in from the Atlantic, cooling the air mass over the UK, and bringing thunder and rain. The breeze will become considerably fresher.