Met Office updates weather warnings with new 12-hour alerts - 31 areas impacted

The Met Office has issued updated weather warnings for rain spanning 12 hours and affecting 31 areas across the country. According to the weather forecaster, heavy rain and thunderstorms may cause some flooding during Saturday afternoon and evening, overnight into Sunday. The warning is in place from 12 noon Saturday to overnight Sunday (July 19).

At present, the country is already under an amber warning for the parts of south east England. The warning area includes London which is particularly susceptible to surface water issues during thunderstorms due to the high proportion of impermeable surfaces. Within this area, 20-40mm of rain could fall in an hour, with up to 70-100mm accumulating in just a few hours.

The Met Office explained: "Outbreaks of heavy rain and isolated thunderstorms are expected to affect southwest England from Saturday evening, gradually spreading further north and east across Wales during early Sunday morning. "Further heavy showers and thunderstorms will break out in places across the warning area through the course of Sunday. Rainfall amounts will vary from place to place, but in some areas 30 to 50 mm is likely to fall in a few hours and there is a small chance that a few locations could see 75 mm or more." Brits are likeky to face power cuts with a possibility of loss to other services to homes and businesses. "Where flooding occurs, there is a slight chance of delays or cancellations to train and bus services," the Met office warned.

Met Office Chief Meteorologist, Andy Page, said: "Intense rainfall will impact parts of the UK as thunderstorms move in from France. A range of severe weather warnings have been issued, including an Amber warning covering southeast England and London. The intense rainfall could lead to surface water flooding as well as frequent lightning and hail too.

"The situation is evolving, and warnings may be changed or added. This weekend is expected to be busy on the roads as more schools in England and Wales break up for the summer holidays, so it's important people keep up-to-date with the very latest forecast.

"There will be spells of more pleasant weather in parts of the UK through the weekend, with some sunny spells in between systems as they move through."

London & South East England

• Hampshire

South West England

• Bath and North East Somerset
• Bournemouth Christchurch and Poole
• Bristol
• Cornwall
• Devon
• Dorset
• Gloucestershire
• Isles of Scilly
• North Somerset
• Plymouth
• Somerset
• South Gloucestershire
• Torbay
• Wiltshire

Wales

• Blaenau Gwent
• Bridgend
• Caerphilly
• Cardiff
• Carmarthenshire
• Ceredigion
• Merthyr Tydfil
• Monmouthshire
• Neath Port Talbot
• Newport
• Pembrokeshire
• Powys
• Rhondda Cynon Taf
• Swansea
• Torfaen
• Vale of Glamorgan