Red heat health alerts are in place across England, from London to Manchester, while orange warnings cover the whole of Wales and southern Scotland.
But where was the hottest place in the country on Monday (July 18) – and where could the highest temperatures reach today (Tuesday July 19)?
Here’s everything you need to know.
Was it hot on Monday?
NationalWorld took observations from both the Met Office and the Windy weather forecast app.
At midday on Monday July 18, the hottest places in the UK (all with temperatures of 34℃) were:
- Greater London
- Bracknel, Berkshire
- working, Surrey
- Fleet, Hampshire
- Chelmsford, Harlow, Bishops Stortford and Braintree, Essex
- Stevenage, Arlesey and Royston, Hertfordshire
- Haverhill, Sudbury and Bury St Edmunds, Suffolk
- Cambridge, Saint Neots, Cambridgeshire
- Tewkesbury, Gloucestershire
- Pershore, Worcestershire
- Bidford, Devon
As of 1 p.m., the hottest places were Cambridge and Barnstaple, where the mercury reached 35℃.
Temperatures soared to 36℃ in the following cities and rural areas as of 3 p.m.:
- Stevenage, Potters Bar, Letchworth, Buntingford and Royston, Hertfordshire
- Rayleigh, Chelmsford, Braintree, Harlow, Bishops Stortford, Thaxted, Saffron Walden and Maldon, Essex
- Bedford and Biggleswade, Bedfordshire
- Haverhill, Lavenham and Bury St Edmunds, Suffolk
- Cambridge, Huntingdon and Linton, Cambridgeshire
- Tewkesbury, Gloucestershire
- Worcester, Upton-upon-Severn, Pershore, Evesham and Droitwich Spa, Worcestershire
Temperatures remained high well into the evening with 35℃ recorded at:
- Waddington, lincolnshire
- Northolt, London
- Rostherne, Eastern Cheshire
The maximum temperatures in the four countries (so far) have been:
- England: 38.1°C at Santon Downham, Suffolk (0.6℃ lower than the all-time temperature record)
- Scotland: 30.8℃ in Aboyne, Aberdeenshire (Scotland’s all-time record temperature is 32.9℃)
- Wales: 37.1℃ Hawarden, Flintshire (tentatively the highest temperature on record in Wales, beating the previous record of 35.2℃)
- North Ireland: 30.9℃ in Derrylin, County Fermanagh (Northern Ireland’s temperature record is 31.3℃ recorded in July 2021)
It was also a record night, with the UK recording its hottest night on record on Monday.
Highs of 25.9℃ were recorded at Emley Moor near Huddersfield, West Yorkshire.
What is the hottest place in the UK?
Tuesday (July 19) should be even warmer than Monday. Temperatures could reach 41℃ in Yorkshire and Lincolnshire, and reach 40℃ in London.
As of 10 a.m., the highest temperatures were recorded at Kew Gardens, West London (35.1℃), Heathrow (34.5℃) and Monks Wood, Cambridgeshire (34.3℃).
The Met Office says provisional data showed Charlwood, Surrey broke the UK temperature record at 11am, posting a high of 39.1℃.
Just before 1pm, Heathrow set the provisional record – breaking the 40℃ barrier for the first time in UK history with a temperature of 40.2℃.
Bedfordshire, Cambridgeshire, Lincolnshire, Nottinghamshire, Yorkshire and the West Midlands are all expected to meet or exceed that temperature this afternoon.
At 4 p.m. – the heat of the day – the mercury is expected to break through the 40℃ barrier at these locations:
- Cambridge, Huntingdon, March and Peterborough, Cambridgeshire
- Stamford, Bourne, Sleaford, Lincoln, Wragby, Horncastle and Scunthorpe, lincolnshire
- Newark-on-Trent, Nottinghamshire
Parts of East Anglia, the East, East Midlands and Yorkshire will be on track for temperatures of 39℃, meaning they too could break the temperature record.
In Scotland, record highs of 34℃ are expected in the border towns of Hawick and Jedburgh from 1pm.
Meanwhile, in Wales, Monmouth and Wrexham are expected to be the hottest places with temperatures expected to reach at least 32℃.
In Northern Ireland, the mercury will peak at 22℃ in Belfast as an Atlantic weather system begins pushing in from the west.
We won’t know if an official temperature record has been broken until Wednesday, July 20 at 10 a.m.
What did the Met Office say about the UK heatwave?
The Met Office called the weather “unprecedented”.
The forecaster said a new temperature record is “very likely” to be recorded.
“We are looking at maximum temperatures somewhere between 40C and 41C, and this is expected to occur in the Lincolnshire and Yorkshire region,” said Met Office meteorologist Annie Shuttleworth.