A whopping 31 counties are to roast tomorrow with temperatures set to sizzle to a boiling 30C in what could be the warmest start to May on record. Following a surge of warmth on Tuesday that brought temperatures close to 25C in parts of England, the unseasonably hot spell is set to continue.

Tomorrow history could be made, with some areas possibly experiencing a blistering 30C. The previous temperature record for the beginning of May was 27.4C in 1990, reports The Times. The Met Office has a specific criterion for what constitutes a heatwave: three successive days with temperatures going beyond the "heatwave threshold", which varies by region but generally starts at 25C in much of the UK.

Millions of Brits are predicted to bask in heatwave conditions tomorrow with WXCHARTS weather maps having turned a blistering red indicating boiling temperatures.

WXCHARTS is predicting slightly lower temperatures than the Met Office. London, Surrey, Essex and Kent are all predicted to see the hottest conditions with 24C-25C predicted at 6pm tomorrow.

The East of England is forecast to have slightly lower temperatures with the mercury set to hover at a warm 23C.

Those in the East Midlands won’t miss out on the heatwave with temperatures to soar to around 22C

Wales will also see the mercury soar with key cities including Cardiff and Swansea predicted highs of 22C.

The full list of UK counties set to reach 22C tomorrow:

England

1. Kent

2. Surrey

3. London

4. Essex

5. Hampshire

6. Wiltshire

7. Hertfordshire

8. West Berkshire

9. West Sussex

10. East Sussex

11. Oxfordshire

12. Buckingshire

13. Bedfordshire

14. Suffolk

15. Norfolk

16. Cambridgeshire

17. Northamptonshire

18. Gloucestershire

19. Warwickshire

20. Leicestershire

21. Lincolnshire

22. Derbyshire

23. Staffordshire

24. Hertfordshire

25. North Yorkshire

26. Cheshire

27. Lancashire

Wales 

1. Powys

2. Monmouthshire

3. Cardiff

4. Vale of Glamorgan

Separately, Nicola Maxey of the Met Office said: “As high pressure continues to dominate the UK weather, we will see the temperatures building day on day through the week, with Thursday seeing the peak of the heat with 29c or even a chance we could see 30c.

"Friday temperatures will start to dip across much of the UK as the high pressure starts to pull away.”