Worrying heat hazard figures have revealed the areas in the UK most at risk during periods of abnormally high temperature.
Satellite data suggests more than six million Brits live in places with a higher risk of dangerously overheating during the summer.
It comes as forecasters predict another heatwave in August after Britain reached record-breaking temperatures of up to 41C last week.
The unprecedented surge saw roads melt and firefighters battling devastating fires due to the extreme weather.
Experts fear climate change will only make matters worse in future as summer temperatures continue to rise and the country scrambles to install more heat-resistant infrastructure.
The summer of 2020 saw the most heatwave-related deaths since records began in 2004 with over 2,200 fatalities in over-65s.
Working in partnership with 4 Earth Intelligence, the Mirror can reveal the full extent of the findings which relate to a phenomenon called the urban heat island effect.
Buildings and roads absorb and retain heat, and become significantly hotter than surrounding areas with shade or green space.
Meanwhile, significant bodies of water have a cooling effect.
Each postcode of every area has been given a ranking between zero and five.
The table then ranks each area by percentage of how many fives it received and also in the second column how many fours and fives.
It reverts to alphabetical order for those that have no fives.
John Lloyd, spokesman for 4 Earth Intelligence He said: “Looking at the rankings of the areas in the UK with the most postcodes at the highest risk from a heat wave, a score of 5, London dominates.
"There are actions that may be taken though to make these postcodes more resilient such as planting more trees, building more parks, and greenifying our buildings, especially rooftops.
"When you include the postcodes with a heat hazard score of 4, the second most at risk, you begin to see more than just London areas show up at the top of the rankings."
Oxford, for example, moves from 44th to first.
And it's often deprived postcodes that are most at risk, according to further analysis combining the stats with relative poverty figures, by the BBC.
People living closer to the poverty line are also statistically more likely to have poorer health and be more vulnerable to the heat.
Anthony Costello, professor of global health and sustainable development at University College London, said: "Anyone with severe illness or underlying conditions, older people, babies and the disabled can get overheated quite quickly.
"If you're in a top floor flat, if you're homeless, if you work outside and you have to do a lot of physical exertion, you are very vulnerable."
Rohinton Emmanuel, professor of sustainable development at Glasgow Caledonian University, adds our homes are not built for regular heatwaves.
Buildings need to be made at different heights to increase shade and create breeze, and more trees need planting, he said.
While green roofs and walls can decrease the amount of heat absorbed by buildings.
He added: "Cities take considerable time to change. We are already late."
Each area of UK ranked by heat hazard threat
- Newham London Boro
- Barking and Dagenham London Boro
- Waltham Forest London Boro
- Brent London Boro
- Hammersmith and Fulham London Boro
- Ealing London Boro
- Wandsworth London Boro
- Redbridge London Boro
- Hackney London Boro
- Hounslow London Boro
- Tower Hamlets London Boro
- Islington London Boro
- Bexley London Boro
- Southwark London Boro
- Haringey London Boro
- Merton London Boro
- Havering London Boro
- Hillingdon London Boro
- Harrow London Boro
- Barnet London Boro
- Lambeth London Boro
- City of Westminster London Boro
- Richmond upon Thames London Boro
- Kensington and Chelsea London Boro
- Croydon London Boro
- Kingston upon Thames London Boro
- Caerdydd - Cardiff
- Enfield London Boro
- Lewisham London Boro
- Camden London Boro
- Greenwich London Boro
- Moray
- Leeds District
- Wrecsam - Wrexham
- Sutton London Boro
- Boston District
- Sir Gaerfyrddin - Carmarthenshire
- Powys - Powys
- Bromley London Boro
- Sir y Fflint - Flintshire
- West Lothian
- City and County of the City of London
- Eastleigh District
- Oxford District
- Wellingborough District
- Sir Benfro - Pembrokeshire
- Surrey Heath District
- Wakefield District
- Castell-nedd Port Talbot - Neath Port Talbot
- Cherwell District
- Gateshead District
- Dumfries and Galloway
- Daventry District
- Casnewydd - Newport
- Sir Ddinbych - Denbighshire
- Test Valley District
- Sheffield District
- City of Leicester
- Sunderland District
- Halton
- Rushmoor District
- Bro Morgannwg - the Vale of Glamorgan
- Dudley District
- West Oxfordshire District
- Vale of White Horse District
- Abertawe - Swansea
- Swindon
- North East Lincolnshire
- Renfrewshire
- Reading
- City of Portsmouth
- Glasgow City
- Falkirk
- Slough
- Scottish Borders
- Pen-y-bont ar Ogwr - Bridgend
- Aberdeenshire
- York
- City of Kingston upon Hull
- Broxbourne District
- West Dunbartonshire
- Milton Keynes
- South Oxfordshire District
- East Riding of Yorkshire
- North Lanarkshire
- Crawley District
- Selby District
- Worthing District
- Stirling
- Havant District
- Darlington
- Bassetlaw District
- Winchester District
- Buckinghamshire
- South Kesteven District
- Doncaster District
- City of Peterborough
- Windsor and Maidenhead
- Solihull District
- Basingstoke and Deane District
- Liverpool District
- Rotherham District
- Central Bedfordshire
- City of Nottingham
- County Durham
- Fife
- Kirklees District
- City of Bristol
- Corby District
- Cotswold District
- East Northamptonshire District
- Kettering District
- North Somerset
- Sedgemoor District
- South Gloucestershire
- South Holland District
- South Northamptonshire District
- Stratford-on-Avon District
- Stroud District
- Aberdeen City
- Adur District
- Allerdale District
- Amber Valley District
- Angus
- Argyll and Bute
- Arun District
- Ashfield District
- Ashford District
- Babergh District
- Barnsley District
- Barrow-in-Furness District
- Basildon District
- Bath and North East Somerset
- Bedford
- Birmingham District
- Blaby District
- Blackburn with Darwen
- Blackpool
- Blaenau Gwent - Blaenau Gwent
- Bolsover District
- Bolton District
- Bournemouth, Christchurch and Poole
- Bracknell Forest
- Bradford District
- Braintree District
- Breckland District
- Brentwood District
- Broadland District
- Bromsgrove District
- Broxtowe District
- Burnley District
- Bury District
- Caerffili - Caerphilly
- Calderdale District
- Cambridge District
- Cannock Chase District
- Canterbury District
- Carlisle District
- Castle Point District
- Charnwood District
- Chelmsford District
- Cheltenham District
- Cheshire East
- Cheshire West and Chester
- Chesterfield District
- Chichester District
- Chorley District
- City of Derby
- City of Edinburgh
- City of Plymouth
- City of Southampton
- City of Stoke-on-Trent
- City of Wolverhampton District
- Clackmannanshire
- Colchester District
- Conwy - Conwy
- Copeland District
- Cornwall
- County of Herefordshire
- Coventry District
- Craven District
- Dacorum District
- Dartford District
- Derbyshire Dales District
- Dorset
- Dover District
- Dundee City
- East Ayrshire
- East Cambridgeshire District
- East Devon District
- East Dunbartonshire
- East Hampshire District
- East Hertfordshire District
- East Lindsey District
- East Lothian
- East Renfrewshire
- East Staffordshire District
- East Suffolk District
- Eastbourne District
- Eden District
- Elmbridge District
- Epping Forest District
- Epsom and Ewell District
- Erewash District
- Exeter District
- Fareham District
- Fenland District
- Folkestone and Hythe District
- Forest of Dean District
- Fylde District
- Gedling District
- Gloucester District
- Gosport District
- Gravesham District
- Great Yarmouth District
- Guildford District
- Gwynedd - Gwynedd
- Hambleton District
- Harborough District
- Harlow District
- Harrogate District
- Hart District
- Hartlepool
- Hastings District
- Hertsmere District
- High Peak District
- Highland
- Hinckley and Bosworth District
- Horsham District
- Huntingdonshire District
- Hyndburn District
- Inverclyde
- Ipswich District
- Isle of Wight
- Isles of Scilly
- King's Lynn and West Norfolk District
- Knowsley District
- Lancaster District
- Lewes District
- Lichfield District
- Lincoln District
- Luton
- Maidstone District
- Maldon District
- Malvern Hills District
- Manchester District
- Mansfield District
- Medway
- Melton District
- Mendip District
- Merthyr Tudful - Merthyr Tydfil
- Mid Devon District
- Mid Suffolk District
- Mid Sussex District
- Middlesbrough
- Midlothian
- Mole Valley District
- Na h-Eileanan an Iar
- New Forest District
- Newark and Sherwood District
- Newcastle upon Tyne District
- Newcastle-under-Lyme District
- North Ayrshire
- North Devon District
- North East Derbyshire District
- North Hertfordshire District
- North Kesteven District
- North Lincolnshire
- North Norfolk District
- North Tyneside District
- North Warwickshire District
- North West Leicestershire District
- Northampton District
- Northumberland
- Norwich District
- Nuneaton and Bedworth District
- Oadby and Wigston District
- Oldham District
- Orkney Islands
- Pendle District
- Perth and Kinross
- Preston District
- Redcar and Cleveland
- Redditch District
- Reigate and Banstead District
- Rhondda Cynon Taf - Rhondda Cynon Taf
- Ribble Valley District
- Richmondshire District
- Rochdale District
- Rochford District
- Rossendale District
- Rother District
- Rugby District
- Runnymede District
- Rushcliffe District
- Rutland
- Ryedale District
- Salford District
- Sandwell District
- Scarborough District
- Sefton District
- Sevenoaks District
- Shetland Islands
- Shropshire
- Sir Ceredigion - Ceredigion
- Sir Fynwy - Monmouthshire
- Sir Ynys Mon - Isle of Anglesey
- Somerset West and Taunton District
- South Ayrshire
- South Cambridgeshire District
- South Derbyshire District
- South Hams District
- South Lakeland District
- South Lanarkshire
- South Norfolk District
- South Ribble District
- South Somerset District
- South Staffordshire District
- South Tyneside District
- Southend-on-Sea
- Spelthorne District
- St. Albans District
- St. Helens District
- Stafford District
- Staffordshire Moorlands District
- Stevenage District
- Stockport District
- Stockton-on-Tees
- Swale District
- Tameside District
- Tamworth District
- Tandridge District
- Teignbridge District
- Telford and Wrekin
- Tendring District
- Tewkesbury District
- Thanet District
- The City of Brighton and Hove
- Three Rivers District
- Thurrock
- Tonbridge and Malling District
- Torbay
- Torfaen - Torfaen
- Torridge District
- Trafford District
- Tunbridge Wells District
- Uttlesford District
- Walsall District
- Warrington
- Warwick District
- Watford District
- Waverley District
- Wealden District
- Welwyn Hatfield District
- West Berkshire
- West Devon District
- West Lancashire District
- West Lindsey District
- West Suffolk District
- Wigan District
- Wiltshire
- Wirral District
- Woking District
- Wokingham
- Worcester District
- Wychavon District
- Wyre District
- Wyre Forest District
