Daniel Wolfram
The calendar is well into the last part of September, but now a possible heatwave is coming to Britain this week.
Autumn is officially here. But no one has told the weather forecasters yet.
For while the trees are preparing to shed their leaves and the warmer clothes are being brought out of the closet, a possible heatwave is threatening to put a heating blanket all over Britain.
And it could last all week.
One last possible heatwave
A massive heat dome is pushing warm air from North Africa into Europe. Forecasters warn that British temperatures could reach as high as 26°C next week in parts of the United Kingdom.
The promise of an Indian summer will bring unusually warm weather back to southern England right as autumn knocks on the door.
“The change begins with developments over the Atlantic. A deep area of low pressure is expected to form well to the west of the UK. Although this system is not forecast to move directly across the country, it is likely to drag warmer air up from the continent and the subtropical Atlantic,” the United Kingdom’s national weather service, the Met Office, explained.
Record summer heat
“The prospect of one final heatwave before the end of the month is certainly not out of the question,” the weather and climate agency noted in a recent update according to The Independent.
This unexpected warmth follows an extraordinary summer season across Europe. Britain recorded its hottest summer in history in 2026, with average temperatures reaching 16.5°C across June, July, and August.
Five separate heatwaves battered the country over those three months. Reservoirs dried up, public health systems faced severe stress, and large areas remain trapped in drought.
Where is it expected to be warmest?
According to the Mirror, Essex, Hertfordshire, and Cambridgeshire are the three counties expected to be warmest this week with temperatures up to 26°C.
Meanwhile, the counties in and around Yorkshire are expected to be the coldest with temperatures in the low 20s.
The Met’s extended weather forecast covering Monday, 21 September to Wednesday, 30 September states that the weather can become very humid as well.
“As such, plenty of dry and increasingly warm and perhaps rather humid weather will develop.”
