Travel disruption is expected today for parts of England and Wales that find themselves under a yellow thunderstorm warning.
The Met Office says delays to train services are likely, while driving conditions could be treacherous.
Flooding is possible, with up to 80mm of rain tipped to fall in three hours in some places, and there’s a risk of damage to buildings.
The warning covers parts of England stretching from Devon to north of Stoke-on-Trent, and spans much of Wales, including Cardiff.
It lasts from 2pm today until 2am on Tuesday.
Get the five-day forecast where you are
The Met Office warns:
• Driving conditions are likely to be affected by spray, standing water, hail and gusty winds, leading to longer journey times by car and bus
• Some flooding of a few homes and businesses likely, leading to some damage to buildings or structures
• Delays to some train services are likely
• Probably some damage to a few buildings and structures from either lightning strikes or gusty winds
• Some short term loss of power and other services is likely
Met Office spokesperson Oli Claydon said the conditions should clear by the weekend, but said there could be an unsettled few days beyond the timescale of the thunderstorm warning.
He explained: “The main factor leading our weather in the next few days and indeed through the week is an area of low pressure that’s coming to the west of the UK.
“And it sits there through the week, very slowly moving eastward.
“From that area of low pressure we’ll get a number of fronts that are sort of spinning off it, as well as the thunderstorms which are being pushed up from the south.
“We’ve also got a cold front that’s moving eastward off of that low pressure, bringing further rain as well.”
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With summer officially over, the conditions represent a stark change from the prolonged dry conditions seen during recent months.
The Met Office confirmed last week that England had just experienced its joint hottest summer on record, with temperatures having climbed above 40C for the first time.
Britons have been warned that future summers are likely to be longer and drier because of climate change.
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