A health alert has been issued for all of England after a heatwave was declared in the UK.
The UK Health Security Agency (UKHSA) and the Met Office has placed a yellow alert on all of England until Monday, 19 June.
Five regions of England were previously placed under an amber alert on Friday which were lowered to yellow at 9am on Tuesday morning.
The Met Office said large parts of the UK was experiencing a heatwave on Tuesday, but it is likely the peak of it has already past with temperatures above 32C recorded on Saturday and Sunday.
The mercury hit 30.1C at Bridgefoot in Cumbria on Tuesday.
Most of the south east, central and the western part of northern England are now in a heatwave according to the Met Office, as well as western Scotland.
A yellow heat health alert means vulnerable people may be at heightened risk due to the weather.
Analysis by ITV Weather Reporter Becky Mantin
After three consecutive days of daily maximum temperatures meeting or exceeding the heatwave threshold, the Met Office has officially declared a heatwave in the UK.
The threshold varies by UK county, see the UK temperature threshold map below.
How long will it last?
It is expected that temperatures will continue to exceed 25C by day fairly widely across the UK for at least the next week
How hot will it get?
Temperatures probably peaked over the last few days with highs of 32.2C at Chertsey in Surrey but it will remain hot.
Generally out to the southern and western parts of the UK as the east will be kept a little cooler thanks to an onshore breeze.
Will we see a return of the thunderstorms?
Very likely. It will remain dry for most in the next 48 hours but as we move through Friday and into the weekend, the risk of showers increases from the southwest - some of these will be very heavy and thundery.
Weather warnings are likely thanks to the huge amount of rain that is can happen during these episodes in a short space of time.
Like this week, these deluges bring the risk of travel impacts and localised flooding.
Why is this happening?
High pressure is in control of our weather at the moment - which is very common in the summer - giving mostly dry, sunny conditions, allowing heat to build over an extended period of time.
What does the Met Office say about whether heatwaves are linked to climate change?
Heatwaves are extreme weather events, but research shows that climate change is making them more likely.
A scientific study by the Met Office into the Summer 2018 heatwave in the UK showed that the likelihood of the UK experiencing a summer as hot or hotter than 2018 is a little over 1 in 10.
It is 30 times more likely to occur now than before the industrial revolution because of the higher concentration of carbon dioxide (a greenhouse gas) in the atmosphere.
As greenhouse gas concentrations increase heatwaves of similar intensity are projected to become even more frequent, perhaps occurring as regularly as every other year by the 2050s.
The Earth’s surface temperature has risen by 1°C since the pre-industrial period (1850-1900) and UK temperatures have risen by a similar amount.
Despite the heat, thunderstorm warnings remain in place in parts of western Scotland and Northern Ireland from 12pm to 9pm.
There is also a flood warning in place along the River Weaver in west Cheshire.
Large parts of England were battered by thunderstorms on Monday evening with Lancashire Fire and Rescue Service said four fire engines were called to a house in Lytham St Annes on Monday night after a lightning strike caused the roof to catch on fire.
Torrential rain also temporarily halted the Manchester City trophy parade, which celebrated the club winning the treble, with the start time pushed back half an hour to 7pm due to the downpours.
The Met Office says the worst of the thunderstorms are now over, with drier weather predicted for the rest of the week.
The 30.1C recorded in Cumbria on Tuesday means every single British summer day (June 1 - August 31) has now recorded a temperature above 30C.
The previous June 13 record was 28.3C in 1948.
Temperatures are expected to remain high for the rest of the week across the country.
The forecast over the next few days by ITV Weather Reporter Becky Mantin
Many areas will have a dry day with very warm or hot sunshine developing. However, scattered thundery showers will break out, mainly across the west of Scotland and Northern Ireland. Winds remaining light and easterly.
Any remaining showers easing through the evening to leave a mostly dry night with clear spells. A little mist in the west. Remaining warm and rather muggy.
Early mist quickly clearing to leave a mostly dry day with plenty of very warm sunshine. The odd shower is possible in the far northwest through the afternoon.
Outlook for Thursday to Saturday:
Most places will be dry and settled with some very warm sunshine, and feeling fresher than of late. However, some showers are possible in the west, more especially on Saturday.
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