London could be in the grips of a heatwave for 10 consecutive days from this weekend, as high pressure building from the Azores pushes temperatures towards 30C and beyond.
Saturday’s forecast shows temperatures hovering around 28C in the capital by 4pm, rising to 31C by Monday, according to The Independent. BBC Weather suggests highs between 28C and 32C that will last from Saturday for a full 10 days.
“Third UK heatwave likely as temperatures forecast to hit 30C, lasting up to 10 days in London.”
The Met Office said a heatwave would be declared once daytime temperatures meet regional thresholds – 28C for three consecutive days in London and the south-east, and 27C across much of the rest of south-east England. In northern Britain the threshold is 25C.
Tony Wisson, Met Office deputy chief forecaster, said: “Toward the weekend, high pressure will continue to build in across most of the UK as it extends from the Azores. This will lead to more settled, warm or very warm conditions for many, especially across England and Wales, though some rain may still affect the far North.”
He added: “The forecast for this weekend suggests that temperatures could approach high twenties across parts of England, perhaps 30C in parts of the southeast, with values of mid- to high-twenties in Wales.”
The UK has already endured two heatwaves this year and smashed the record for the hottest spring ever in England and Wales. Last month was the warmest June on record for England, and the second warmest for the UK as a whole, according to provisional data from the Met Office. A new record temperature was provisionally set in Lingwood, Norfolk, last Friday when the mercury climbed to 37.7C.
The UK Health Security Agency has issued yellow heat health alerts for the East Midlands, East of England, London, south-east and south-west, warning of a greater risk to life for vulnerable people.
Unlike the last heatwave, the air is expected to be less humid, at least initially, so it may feel a little more comfortable despite the high temperatures. Mr Wisson noted: “Although a return to heatwave conditions is looking increasingly likely for some areas, the likelihood of such extreme high temperatures or high levels of humidity as last week is currently low.”
In the south west and Midlands, temperatures will fluctuate between 28C and 30C in Birmingham and 27C in Exeter. But Northern Ireland and western Scotland will see more variable weather, with cloudier conditions and outbreaks of rain, and temperatures peaking at 20C.
The high pressure may be a little further south, allowing fresher Atlantic air and perhaps scattered rain clouds to filter into Northern Ireland, Scotland and northern England. For much of England and Wales, however, the hot spell looks set to tighten its grip.