This article is more than 2 years old

This article is more than 2 years old

As if the national mood needed further dampening after England’s World Cup exit, thunderstorms and heavy rain threaten to end the heatwave that has lasted for almost four weeks.

The Met Office has issued a yellow thunderstorm warning for 11am to 8pm on Friday, putting regions such as London and south-east England, the north-west, south-west, Wales and the West Midlands on notice of a risk of downpours.

Met Office (@metoffice) A yellow severe weather warning for #thunderstorms has been issued for Friday: https://t.co/QwDLMfRBfs Stay #weatheraware @metofficeUK pic.twitter.com/NxpsGepY3v

It is only the second thunderstorm warning to be issued since the new alert was introduced last month and it states that heavy showers in some places could bring “around 20mm (0.8in) in an hour”, while other areas will remain dry.

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The forecast will be welcomed by gardeners but threatens to bring to an end a spell of hot weather during which temperatures of more 30C (86F) have been recorded for three weekends in a row.

On Thursday many people across the country will still be able to enjoy a very warm day of 27C to 28C (80.6F-82.4F). But from Friday the temperature could drop to about 20C in areas hit by thunderstorms and further east.

The Met Office meteorologist Martin Bowles said the areas that could be heaviest hit include Wales and central southern England.

“You can get a lot of rain in a short time. You can get flooding issues with people driving on roads facing large puddles,” he said. “It is a ‘be prepared’ warning so it is not expected to cause problems but people need to be aware of it.”

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The warning says: “Heavy showers, which will most likely become thundery in places, are expected to develop quite widely across parts of England and Wales later Friday morning and through the afternoon.

“Some of the showers are likely to become focused into slow-moving bands, particularly over south-west England, with some locations receiving around 20mm in an hour.

“As is the nature of showers, however, many places within the warning area will miss them altogether, and have a dry day.”