The Met Office has issued a yellow weather warning for much of England and Wales, including London.
The warning will be in place from 10am today (Monday 15) until Wednesday, August 17.
Other regions affected by the weather warning include the North West, South West, West Midlands, Yorkshire & Humber and more.
A Met Office spokesperson said: "Thunderstorms and areas of heavy rain will develop quite widely across much of England and Wales.
"The extent of these thunderstorms will be more widespread than on Monday, though some spots will still miss storms and remain dry.
What do weather warnings mean?
"20-30 mm of rain is possible within an hour, but where areas of thundery rain become slow-moving, some places could see 50 mm in less than three hours.
"There is a chance that higher totals could occur in a few spots over the course of the day.
"Hail and frequent lightning are likely additional hazards for some places."
Met Office issues yellow weather warning for thunderstorms in London
In terms of what to expect, the Met Office has said:
- Spray and sudden flooding could lead to difficult driving conditions and some road closures
- There is a chance that homes and businesses could be flooded quickly, with damage to some buildings from floodwater, lightning strikes, hail or strong winds
- There is a slight chance that power cuts could occur and other services to some homes and businesses could be lost
- There is a small chance of fast flowing or deep floodwater
- Where flooding or lightning strikes occur, there is a chance of delays and some cancellations to train and bus services
You can view the forecast via the Met Office website.
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