The Met Office has issued a yellow weather warning for Thursday, August 27, covering the UK from northern England to London, with possible power cuts and travel disruption.
The forecaster said "spray and sudden flooding could lead to difficult driving conditions and some road closures," and added that "there is a slight chance that power cuts could occur, and other services to some homes and businesses could be lost."
Advice and hazards
"People cope better with power cuts when they have prepared for them in advance. It's easy to do; consider gathering torches and batteries, a mobile phone power pack and other essential items", the advice from the Met Office added.
Lightning and hail of 1-2 cm will also be hazards, the Met Office added.
Forecast details
The full forecast read: "A band of thunderstorms and heavy rain will move north across England and Wales, perhaps becoming slow-moving in the afternoon and evening.
"Accumulations of 20-30 mm in three hours can be expected fairly widely, and up to 50 mm in a 12-hour period can be expected in places.
"There is a small chance that some places may see more than 50 mm in three hours and more than 75 mm through 12 hours, especially over east-facing high ground. Lightning and hail of 1-2 cm will also be hazards."
Additional warnings
A warning for thunderstorms is also in place today until 10pm as "a band of heavy showers and thunderstorms is expected to move northwards".
Thunderstorms may be intense, with 20-30 mm of rain falling in less than an hour and perhaps 40-50mm in 2-3 hours in a few spots, leading to some surface water flooding, a Met Office forecast said.
Areas covered by the power cut warning
East Midlands: Derby, Derbyshire, Leicester, Leicestershire, Lincolnshire, Northamptonshire, Nottingham, Nottinghamshire, Rutland.
East of England: Bedford, Cambridgeshire, Central Bedfordshire, Essex, Hertfordshire, Luton, Norfolk, Peterborough, Suffolk.
London & South East England: Buckinghamshire, Milton Keynes, Oxfordshire.
North West England: Blackburn with Darwen, Cheshire East, Cheshire West and Chester, Greater Manchester, Halton, Lancashire, Merseyside, Warrington.
South West England: Bristol, Gloucestershire, North Somerset, South Gloucestershire, Swindon, Wiltshire.
Wales: Blaenau Gwent, Bridgend, Caerphilly, Cardiff, Carmarthenshire, Ceredigion, Conwy, Denbighshire, Flintshire, Gwynedd, Isle of Anglesey, Merthyr Tydfil, Monmouthshire, Neath Port Talbot, Newport, Powys, Rhondda Cynon Taf, Torfaen, Wrexham.
West Midlands: Herefordshire, Shropshire, Staffordshire, Stoke-on-Trent, Telford and Wrekin, Warwickshire, West Midlands Conurbation, Worcestershire.
Yorkshire & Humber: East Riding of Yorkshire, Kingston upon Hull, North East Lincolnshire, North Lincolnshire, North Yorkshire, South Yorkshire, West Yorkshire, York.
