Met Office weather: ‘Torrential rain’ as yellow thunderstorm warning now includes London

A Met Office yellow weather warning for thunderstorms now includes London, with the capital facing “torrential downpours” and a risk of disruption from “sudden flooding”.

Forecasters issued the national warning on Friday, August 12, for much of the UK, excluding the city.

But on Saturday, August 13, predictions were updated to include London within the zone set to be affected by the “hit-and-miss thunderstorms” forecasts for the start of the week.

It comes after a second blazing heatwave scorched the city in baking 36C temperatures, with parks turning brown and the River Thames drying up at its source, amid an official drought being declared.

However, despite the weather warning, which covers England, Wales, Northern Ireland, and much of Scotland, being extended, London is not guaranteed to see rainfall.

Chances of rain are estimated at 10% for much of the day today (Monday, August 15), while forecasts rise to 40% on Tuesday, and 60% on Wednesday.

The weather warning is set to last until 11.59pm on Wednesday.

Londoners should watch out for “hit-and-miss thunderstorms likely to develop through Monday, producing some torrential downpours for some spots, and possible disruption”.

What does the Met Office say to expect?

On Monday, some showers are predicted to start the day, but these are likely to become more widespread and heavier through the late morning and afternoon.

These could see:

• Spray and sudden flooding causing difficult driving conditions and road closures;
• Chance homes and businesses could be flooded quickly;
• Damage to some buildings from floodwater, lightning strikes, hail or strong winds;
• Flooding or lightning strikes risk of delays and cancellations to train and bus services;
• Risk of power cuts and loss of services to some homes and businesses.

In some places, rainfall could even last into the evening.

Where storms occur, slow-moving torrential downpours could produce 20-30mm inside an hour, with 40-50mm falling in around two or three hours, with hazardous hail and lightning.

What has Sadiq Khan said?

Speaking to the BBC Local Democracy Reporting Service (LDRS) on Friday, the mayor of London Sadiq Khan said he was concerned about flash flooding in the coming weeks.

Mr Khan said: “Just over a year ago we saw flash flooding in London that affected people’s homes, businesses, Tube stations.

“I’m really concerned that we could see extreme hot weather followed by really short periods of massive rain.

“We saw last year, I think, two months’ worth of rain in two hours. I don’t think we can ever be prepared for that, because we’re a city not used to that level of rain in a short period of time.

“And, again, that’s one of the consequences of climate change that we’ve got to recognise.

“These are things happening far more regularly than they did previously.”

He added: “We are coordinating with councils what we’d do if that [flooding] was to happen, but let’s be frank, a city like London is not ready for the consequences of climate change and we’ve got to get ready.

“That’s why we’re doing what we can, but we need the government to be on our side as well.”

For more information, visit the Met Office.