The Met Office has issued a rare red extreme heat warning for Wednesday and Thursday, with temperatures forecast to reach at least 39°C, breaking the June all-time daily record. The red warning coincides with an existing amber extreme heat warning covering much of southern and central England and much of Wales until the end of Thursday.
Why filling your freezer matters
Households across England and Wales are being urged to fill their freezers before Wednesday to prepare for possible power cuts. A full freezer is much more energy efficient than an empty one and better equipped to stay cold during a power cut. The frozen food creates a solid thermal mass that holds the cold temperature longer, and less empty space means warm air cannot circulate as easily.
During a power cut, a full freezer can keep food frozen for up to 48 hours, while a half-full freezer only maintains its temperature for around 24 hours.
Expert advice from Anthony Mellor
Anthony Mellor at Swinton Home Insurance said: “Keeping your freezer full is also more energy-efficient than an empty one. A full freezer minimises the amount of warm air that can enter when you open the freezer door, plus the frozen contents help cool any warm air that does get in. This means less energy is required to bring the temperature back down.”
He added: “If that wasn’t a big enough incentive, according to the Food Standards Agency, if you were to ever experience a dreaded power cut, a freezer that is half full would hold food safely for 24 hours, but this doubles to 48 hours if completely full.”
Health and travel impacts
The hot and humid weather is expected to cause population-wide adverse health effects, delays to road, rail and air travel, as well as possible power cuts and loss of other essential services such as water, electricity, gas or mobile phone services. The Met Office advises gathering torches, batteries, a mobile phone power pack and other essential items in advance.
Areas under red and amber warnings
The following 98 areas of England and Wales are covered by the red and amber extreme heat warnings on Wednesday and Thursday, when possible power cuts could occur:
East Midlands: Derby, Derbyshire, Leicester, Leicestershire, Lincolnshire, Northamptonshire, Nottingham, Nottinghamshire, Rutland.
East of England: Bedford, Cambridgeshire, Central Bedfordshire, Essex, Hertfordshire, Luton, Norfolk, Peterborough, Southend-on-Sea, Suffolk, Thurrock.
London & South East England: Bracknell Forest, Brighton and Hove, Buckinghamshire, East Sussex, Greater London, Hampshire, Isle of Wight, Kent, Medway, Milton Keynes, Oxfordshire, Portsmouth, Reading, Slough, Southampton, Surrey, West Berkshire, West Sussex, Windsor and Maidenhead, Wokingham.
North West England: Blackburn with Darwen, Blackpool, Cheshire East, Cheshire West and Chester, Greater Manchester, Halton, Lancashire, Merseyside, Warrington.
South West England: Bath and North East Somerset, Bournemouth Christchurch and Poole, Bristol, Cornwall, Devon, Dorset, Gloucestershire, North Somerset, Plymouth, Somerset, South Gloucestershire, Swindon, Torbay, Wiltshire.
Wales: Blaenau Gwent, Bridgend, Caerphilly, Cardiff, Carmarthenshire, Ceredigion, Conwy, Denbighshire, Flintshire, Gwynedd, Isle of Anglesey, Merthyr Tydfil, Monmouthshire, Neath Port Talbot, Newport, Pembrokeshire, Powys, Rhondda Cynon Taf, Swansea, Torfaen, Vale of Glamorgan, Wrexham.
West Midlands: Herefordshire, Shropshire, Staffordshire, Stoke-on-Trent, Telford and Wrekin, Warwickshire, West Midlands Conurbation, Worcestershire.
Yorkshire & Humber: East Riding of Yorkshire, North Lincolnshire, North Yorkshire, South Yorkshire, West Yorkshire.
Defrost your freezer to save energy
Anthony Mellor also advised: “Ice build-up makes your freezer’s motor work harder and longer to maintain its temperature, consuming more electricity. In contrast, a defrosted freezer runs more efficiently and consumes less energy. To keep your machine running well, defrost when the frost build-up covers a large area and exceeds ¼-inch (0.6cm) thickness.”
