The Met Office issued two yellow weather warning for thunderstorms, affecting eight regions of Britain. The national weather agency warns that thunderstorms could disrupt transports and infrastructure through Friday afternoon and evening (between 12pm and 8pm) in parts of the East Midlands, Yorkshire and the Humber and Northeast England. Another alert active between 9pm on Friday and 6pm Saturday suggests parts of the East of England, East Midlands, London and the Southeast, Northeast England, Northwest England, Southwest England, the West Midlands and Yorkshire and the Humber will be hit.

“Showers and thunderstorms will develop across parts of northern England early Friday afternoon, before becoming concentrated across parts of northeast England,” experts said. Forecasts suggest that 15-25 mm of rain is possible in less than an hour, and “should storms become aligned across similar areas, 40-60 mm of rain is possible, with these higher totals most likely over the North York Moors”. Along with rain, “frequent lightning and large hail are possible,” the Met Office said, and storms are expected to ease and clear into the North Sea on Friday evening.

Regarding Saturday’s warning, forecasters added: “Thundery rain will reach the south of the warning area later Friday before spreading north to affect much of England through Saturday. Rain will likely be locally torrential, bringing 20-30 mm in less than an hour in many places, with 60-90 mm in less than three hours possible in a few places. Whilst rain will clear from the south of the area by early Saturday afternoon, further thunderstorms are likely to develop here.

“As well as heavy rain, impacts from frequent lightning, gusty winds and large hail are also likely.”

Specialists have advised members of the public to consider if their location is at risk of flash flooding, and, if so, consider preparing a flood plan and an emergency flood kit.

The Met Office added: “Give yourself the best chance of avoiding delays by checking road conditions if driving, or bus and train timetables, amending your travel plans if necessary.

“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.”

If you find yourself outside and hear thunder, it is best to protect yourself by finding a safe enclosed shelter, like a car, for example.

Those in the know have told residents not to shelter under or near trees, or other structures which may be struck by lightning. If you are on an elevated area move to lower ground, they add.

The Met Office also said that locals should be prepared for weather warnings to change quickly, and, when a weather warning is issued, experts recommends staying up to date with the weather forecast in your area.

Full list of regions and local authorities included in Friday warning

East Midlands

North East England

• Darlington
• Durham
• Hartlepool
• Middlesbrough
• Redcar and Cleveland
• Stockton-on-Tees

Yorkshire and the Humber

• East Riding of Yorkshire
• Kingston upon Hull
• North East Lincolnshire
• North Lincolnshire
• North Yorkshire
• South Yorkshire
• West Yorkshire
• York

Full list of regions and local authorities included in Saturday warning

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 and Southeast 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

Northeast England

• Darlington
• Durham
• Gateshead
• Hartlepool
• Middlesbrough
• Newcastle upon Tyne
• North Tyneside
• Northumberland
• Redcar and Cleveland
• South Tyneside
• Stockton-on-Tees
• Sunderland

Northwest England

• Blackburn with Darwen
• Cheshire East
• Cheshire West and Chester
• Cumbria
• Greater Manchester
• Halton
• Lancashire
• Merseyside
• Warrington

Southwest England

• Bournemouth Christchurch and Poole
• Dorset
• Gloucestershire
• Swindon
• Wiltshire

West Midlands

• Herefordshire
• Shropshire
• Staffordshire
• Stoke-on-Trent
• Telford and Wrekin
• Warwickshire
• West Midlands Conurbation
• Worcestershire

Yorkshire and the Humber

• East Riding of Yorkshire
• Kingston upon Hull
• North East Lincolnshire
• North Lincolnshire
• North Yorkshire
• South Yorkshire
• West Yorkshire
• York