Three yellow warnings have been issued for parts of the UK as thunderstorms are set to sweep the country today.
The Met Office warned of “heavy rain” and said flooding in “a few homes and businesses” is likely.
There may also be disruption to power and journeys by road.
Much of the south of England and Wales are covered by the warning for thunderstorms, including London, Cardiff, Birmingham and the east coast – with eight regions hit with the warnings in total.
Brits in the affected areas are advised to put together a “flood kit” to prepare for the overwhelming rain to seep into their homes.
The weather agency also suggests keeping valuables, such as electrical devices and documents, high up and out of harm’s way.
It is also worth seeking flood advice to find out where near you is likely to be affected.
As much as 40mm of rain over 2-3 hours could fall in some places, the agency said.
The rain comes as much of Europe is hit with extreme heat in unusual weather that is being widely attributed to climate change.
Brits are being warned: “Probably some damage to a few buildings and structures from lightning strikes.
“There is a good chance driving conditions will be affected by spray, standing water and/or hail, leading to longer journey times by car and bus. Delays to train services are possible. Some short term loss of power and other services is likely.”
Meanwhile, the north east of England is also facing a yellow warning for rain, while an alert for high winds has been put in place for the south coast.
The Met Office said: “Unseasonably windy weather will affect coastal southern England on Wednesday, leading to some disruption to travel and outdoor activities.”
The adverse conditions will continue into Thursday, it added, saying: “Brisk northerly winds on Thursday. Bright or sunny spells with patchy rain in the north. Showers developing elsewhere, occasionally heavy with thunder possible.”
Scroll down for a full list of the areas impacted by the yellow weather warnings today.