The UK is in the grip of a heatwave, with the Met Office issuing a 36-hour red weather warning for 50 areas10:24, 25 Jun 2026Updated 10:25, 25 Jun 2026UK households are being urged to check in on relatives' telephone connections before the heatwave comes to an end, with scorching temperatures expected to continue for much of the remainder of this week. The Met Office has issued a 36-hour red weather warning covering 50 areas across the UK, though even regions outside the warning zone can expect temperatures to soar above 30C right through to Saturday.‌In London, forecasters are predicting highs of 34C on Thursday, 37C on Friday and 32C on Saturday, before finally cooling to 'just' 26C on Sunday.‌Further north in Leeds, Wednesday will bring temperatures of 31C, climbing to 33C by Friday, then easing back to 29C on Saturday and 23C on Sunday.‌Experts are cautioning that prolonged periods of extreme heat can heighten the risk of infrastructure disruption, making it essential that vulnerable people are aware of how their phone service would function during a power cut, as millions of homes continue the switch to digital landlines, reports the Express.The alert comes as millions of households are being migrated from conventional landlines to internet-based digital voice services as part of the UK's nationwide telephone network overhaul.‌Unlike traditional landlines, which drew their power directly from the telephone network, digital phone services are dependent on broadband equipment and mains electricity within the home. Should power be lost, phone services could be affected unless alternative arrangements are already in place.More than three million UK households have already been moved to digital landline services, with the nationwide switch set to be finished by January 2027. The matter is especially worrying for older adults, people living alone and vulnerable residents who depend on their home phone to contact family members, carers or emergency services.Recent Government figures suggest around two million vulnerable people across the UK rely on telecare alarms and related services that have historically used traditional landline connections.‌Bryn Thompson, Director at digital voice provider Phonely, said: "Many people still assume their home phone will continue working during a power cut because that's how landlines operated for generations. But millions of households have already been switched to digital phone services, and many families don't realise there can be important differences during an outage."The current heatwave and Met Office warnings should act as a reminder for families to check how elderly relatives would stay connected if the power goes out."He added: "For older people who depend on a landline as their primary way of staying in touch, a prolonged power cut could become a serious concern if they haven't prepared in advance".‌The UK's analogue Public Switched Telephone Network (PSTN) is being phased out and replaced with modern digital technology, meaning millions of households will transition to digital voice services over the coming months. Although communications providers have put safeguards in place for vulnerable customers, awareness of the switchover among consumers remains worryingly low.Mr Thompson added: "Most households won't experience any problems, but families should take a few minutes to understand how elderly relatives would stay connected during an emergency."Many people don't realise there are simple steps that can reduce the risk of being cut off during a power outage, whether that's having a battery backup, keeping a mobile phone charged, or understanding what support is available from their provider.Article continues below"For many older people, a home phone is far more than a convenience. It's often their main connection to family, carers and emergency support."A simple conversation now could make all the difference if there's an unexpected power outage in the future."