The Met Office has issued its first ever red weather warning ahead of an "exceptional hot spell" early next week.
Applicable to Monday and Tuesday - July 18 and 19 - the warning covers an area from London to Manchester and then up to the Vale of York.
Met Office spokesman Grahame Madge warned of the dangers to come.
“We’ve just issued a red warning for extreme heat for Monday and Tuesday which is the first such warning ever issued," he said.
“This is potentially a very serious situation.”
The warning spells out a number of consequences to these temperatures, including "population-wide adverse health effects" and "substantial changes in working practices".
Risks associated with an influx of people to coastal areas is also cited as a concern, as are likely delays to various forms of travel.
The red warning is to run until 11.59pm on July 19.
An amber warning has been issued for Sunday, July 17.
Both warnings come after a week in which the UK has seen some of its hottest temperatures so far this year.
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