Red weather warning: Met Office issues first ever red weather warning for extreme heat as mercury set to rocket to 40C

Brits are being warned of an “exceptional hot spell on Monday and Tuesday leading to widespread impacts on people and infrastructure.”

Temperatures of 40C are being forecast in England for the first time ever, with extreme heat to grip the country on Monday July 18 and Tuesday July 19.

Met Office spokesman Grahame Madge said there is a 50% chance of temperatures reaching 40C somewhere in the UK, likely along the A1 corridor.

An amber warning for extreme heat remains in place for Sunday July 17.

The red warning covers much of Yorkshire, including York, Leeds, Doncaster, and Selby, while the rest of the region remains under the amber warning.

On Tuesday - expected to be the hotter of the two days - Leeds could see highs of 36C, while York is forecast temperatures of up to 35C, and Doncaster could sizzle in up to 37C heat.

The Met Office warned that the extreme heat could cause people across the UK to fall seriously ill with danger to life - and this would not be limited to those most vulnerable to extreme heat.

It added that substantial changes in working practices and daily routines would be required across the two days, and there will likely be delays on roads and road closures, alongside delays and cancellations to trains and planes.

Furthermore, essential services and mobile phone networks could be compromised by potential loss of power if heat-sensitive systems should fail.

The UK Health Security Agency has increased its heat health warning from level three to level four – a “national emergency”.

"Level four is reached “when a heatwave is so severe and/or prolonged that its effects extend outside the health and social care system…. At this level, illness and death may occur among the fit and healthy, and not just in high-risk groups”, it said.

Forecasters say there is an 80% chance of the mercury topping the UK’s record temperature of 38.7C (101.7F) set in Cambridge in 2019, with the current heatwave set to peak on Tuesday.

Mr Madge said: “We’ve just issued a red warning for extreme heat for Monday and Tuesday which is the first such warning ever issued.

“The warning covers an area from London up to Manchester and then up to the Vale of York.

“This is potentially a very serious situation.”

He said computer modelling had been “firming up around just how intense the heat will be for Monday and Tuesday, with the emphasis on Tuesday”.

“It’s now considered 80% chance we will see the all-time UK record broken,” Mr Madge said on Friday morning.

“There’s stronger indications now of 50% chance of seeing 40C being observed somewhere in the UK, and most likely that would be within the red warning area for extreme heat.

“Probably the most likely areas to look at would be north of London and up to Lincolnshire, inland.

“Somewhere like Peterborough, Grantham, Sandy, Stevenage, those sorts of areas, A1 corridor.”

He said temperatures reaching 40C would be “historic”.

“If we get to 40C, that’s a very iconic threshold and shows that climate change is with us now,” he said.

“This is made much more likely because of climate change.”