After basking in the year's hottest temperatures at the end of the week, Britain is now braced for torrential downpours and storms that could cause flash flooding across large parts of the country.
The Environment Agency has warned almost every county in England and Wales is at "medium" risk of flooding, and has issued dozens of flood alerts, the majority of which are in the Midlands, South West and South East.
It will generally be an unsettled day across the British Isles today. Areas of heavy showers and thunderstorms, which will be severe in places, will move northwards across many parts.
Some drier and brighter spells are also expected and it will continue to feel humid.
Temperatures becoming very warm, locally hot in the east, with highs of 27C (81F).
Viewers have posted dramatic pictures of the storms which ravaged the UK last night. The photos were posted on the ITV News Facebook page.
It seems thousands of people were woken up by loud claps of thunder, seemingly constant flashes of lightning and torrential rain.
Britain is set to bask in the sunshine in the next few days with health officials issuing guidance on how to stay safe in the sunshine.