Heatwave sparks travel chaos as lightning and floods leave commuters facing severe delays and train cancellations

Passengers have been told to expect longer journey times after heavy rain poured down on England overnight as loud thunderstorms roared, and thousands of pangs of lightning struck.

Forecasters say the extreme weather is the result of a “heat dome”, which comes as the UK braces for temperatures of up to 40C over the next few days. 

The Met Office has issued a rare red weather forecast for six regions in England until Sunday.

On the London Underground, the air-conditioned Circle and District lines have been completely suspended following heavy rainfall as Londoners brace for the scorching heat.

There are also severe delays on the Hammersmith & City line and the Elizabeth line.

Flooding has resulted in suspended services between Heathrow Terminal 4 and Heathrow Terminals 2 & 3, and forced Balham Station to close completely.

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Meanwhile, intense lightning and thunderstorms last night forced flights at Bristol Airport to be grounded while flooding swept the South West.

“Following the earlier electrical storm, Bristol Airport remains closed to arriving and departing aircraft whilst engineers investigate a fault with air traffic control systems.

“Customers should contact their airline with any specific flight queries,” an airport spokesperson said. 

Thousands of lightning strikes were reported across Somerset, sparking power outages in the town of  Shepton Mallet while floodwaters left the streets of Bath submerged.  

Parts of Somerset were issued flood alerts near Shepton Mallet and Glastonbury due to the “intense rainfall”.A spokesman for the Met Office said: “These storms brought frequent lightning, with over 23,000 strikes recorded, and up to 35 mm of rain falling in a short period across parts of Somerset, leading to some localised flooding.”

Meanwhile, heavy, thundery showers are ongoing in parts of the southeast, the Met Office said.

Temperatures for the latest heatwave are likely to overtake the June record set in Hampshire in 1976 by several degrees and could come close to the UK’s all-time high of 40.3C which was measured in July 2022.

The hot conditions, which have been very rare in the UK until now, will be accompanied by high humidity and very warm nights, which will make it hard for people to recover overnight, the forecaster warned.

A red weather warning for extreme heat covering an area stretching from London to Swansea and Somerset to Birmingham was issued by the Met Office from 9am on Wednesday to 9pm on Thursday.

These are reserved for the most severe events, the Met Office said, meaning this heatwave is expected to bring “severe and significant impacts” including widespread health risks for many, not just those who are normally more vulnerable to the heat, and even danger to life.

Scores of schools across England and Wales announced they would close or finish early on several days this week to protect pupils amid the extreme heat.

The chief of the London Ambulance Service told LBC that we "are all at risk" and urged people to stock up on potentially life-saving medicine amid the heatwave. 

Craig Harman, chief operating officer of London Ambulance Service NHS Trust, told LBC that his colleagues are expecting a 50% increase in demand this week as he issued stern advice for staying out of danger in extreme heat.

He also urged people to 'stay away from the water' and stay away from swimming in unsupervised bodies of water such as rivers and lakes.

The trust has already received around 7,000 calls per day across the weekend and into Monday, and a 16% rise in calls for patients fainting, before the extreme heat is due on Wednesday and Thursday.

The London Ambulance Service usually takes around 5,500 calls on a typical day.