Swathes of the country are told to expect heavy downpours and thunderstorms, which could see power cuts and train cancellations.
The summer of extreme weather is set to continue as parts of the UK brace themselves for an afternoon of thunderstorms that could close roads, cut power and cause flash flooding to homes and businesses.
The Met Office has issued a yellow weather warning for the east and north east of England, as well as the East Midlands and Yorkshire and Humber, with up to 1.2 inches (30mm) of rain expected to fall in just an hour.
Forecasters are warning of floods and the possibility of damage from lightning strikes and hail, just a week after much of the country was basking in temperatures as high as 32C (89.6F).
Bus and train services could also be disrupted.
The warning is in place until 10pm, but the Met Office has said the “unsettled weather” will continue until later this week.
“We’ve got some unsettled weather continuing for the next few days,” said Luke Miall.
“Quite a contrast really to what much of this summer has seen across the UK.”
It is not the first weather warning to have been put in place for today.
On Sunday, the Met Office issued warnings for the North East, North West, Yorkshire and Humber, Dumfries and Galloway, and Lothian and Borders.
Parts of the country endured some heavy downpours over the weekend, with images on social media showing roads awash with floodwater in Liverpool.
The thunderstorms and showers follow a summer of relentless sunshine and heat, which led to several hosepipe bans.
So far today, temperatures have hovered in the 19C to 22C (66F to 72F) range in Wales, England and Northern Ireland, and slightly lower at 15C to 17C (59F to 63F) in Scotland.
But it is not all doom and gloom, with Sky News weather presenter Jo Edwards expecting parts of the country not affected by the storms to enjoy some fine and sunny conditions.