Temperatures could soar to 35C in some parts of the country today which would make it the hottest day of the year so far.
Warm European air caused temperatures to climb across much of the country on Sunday – and the Met Office has said highs of 34C to 35C could be reached on Monday.
“It’s going to be hot,” Met Office forecaster Craig Snell said.
“The weather is coming with a lot of humidity, so it will feel quite uncomfortable out there across central eastern England.
“Elsewhere, it’s still going to be warm and humid, but the hottest weather will be in central eastern England.”
It comes despite the Met Office issuing two yellow weather warnings for thunderstorms for parts of northern England, Scotland and Northern Ireland.
London, East Anglia and the home counties will experience the warmest weather, with highs of 33C expected in London, 26C in Manchester and 21C in Edinburgh.
The hottest day of 2024 so far was 19 July, when temperatures reached a 31.9C in central London.
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Yellow heat health alert in place
Last week forecasters suggested remnants of Storm Debby in the US could impact the UK’s weather – with the system altering the position of the jet stream – leading to hotter conditions.
A yellow heat health alert is in place for the East and West Midlands, East of England, South East, West, North West and London until Wednesday morning, the UK Health Security Agency has said.
The alert suggests the hot weather may have a minor impact on health and the social care sector.
The Met Office has also recommended people keep curtains closed during the hottest part of the day and drink lots of water.
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Weather warnings in place
But not everyone across the UK will experience the sizzling weather, with two separate warnings in place for storms.
Pic: Met Office
Drivers have been warned to expect spray on the roads and some road closures during the early morning rush hour, amid a “combination of frequent lightning, heavy rain, hail and short periods of strong winds”.
The warning across northern England and Scotland is in place until 1pm on Monday – while the one in Northern Ireland runs until 7am.
Conditions could be ‘nasty’
“Thunderstorms are already beginning to move into the Republic of Ireland,” Mr Snell said late on Sunday evening.
“They will start to move up into Northern Ireland later this evening and then move across Scotland and northern England as we go through the night and into tomorrow.
“It could be potentially quite nasty in places up there.”
Temperatures are expected to cool down through Tuesday and into Wednesday.
The hot weather is not considered a heatwave, the Met Office said, as temperatures need to exceed a specific threshold over three consecutive days in order to meet the criteria.
Temperatures are unlikely to exceed the 40.3C recorded at Coningsby, Lincolnshire, on 19 July 2022, the highest temperature ever recorded in the UK.