Met Office advice to 'avoid using landline' as 22 UK counties face thunderstorms

Thunderstorms and hail are possible in some parts of the UK today, despite temperatures surging to 26C earlier in the week. The Met Office forecast says conditions today will be “wet across northeast England and southern Scotland ” to begin with, while “hail and thunder ” are possible in southern England and Wales. It is expected to “feel humid” for many. Heading into this evening, the Met Office says showers will largely subside overnight before conditions turn “mainly dry”. “Chilly” weather is expected in the north where frost could develop in rural areas. Weather mapping service Ventusky shows there is a possibility of thunderstorms across a large swathe of southern England and Wales at around 7pm this evening. The data suggests they are possible in 22 counties/principal areas. Radnorshire Brecknockshire Glamorgan Monmouthshire Ceredigion Carmarthenshire Herefordshire Gloucestershire Cornwall Devon Somerset Dorset Wiltshire Berkshire Oxfordshire Buckinghamshire Bedfordshire Hertfordshire Middlesex Essex Kent Suffolk The Met Office has published advice for people facing thunderstorms. Before thunderstorms occur, it urges people to “unplug any non-essential appliances” as lightning can cause power surges. You should also “keep away from underground or low-lying spaces such as car parks, basements or underpasses” as flooding can occur rapidly. During a thunderstorm, the Met Office says you should “try to avoid using the landline, unless in an emergency” as telephone lines can conduct electricity. “Avoid activities such as golf , rod fishing or boating on a lake,” it adds. If you find yourself driving in a thunderstorm, it is advised that you wind up the windows and stay inside your car. In the vast majority of cars with a metal roof and frame, the frame will act as a conductive Faraday cage, passing the current around the passengers inside and on to the ground. The Met Office says soft-top convertibles "are the most at risk and could catch fire if struck by lightning". You should also be aware that current can travel through other parts of modern cars, including GPS and radio systems. "Cars with metal interior handles, foot pedals and steering wheels can also carry current," the advice states.