Train services disrupted across UK amid soaring temperatures – here are the affected lines

Train services across Britain are facing disruptions as rising temperatures force Network Rail to impose speed restrictions between lines for safety purposes.

South Western Railway (SWR) has issued a general warning to all passengers, warning that services across its entire network may be “revised” on Tuesday due to hot weather.

Some afternoon and early evening services have already been cancelled.

This affects key routes including journeys between London Waterloo and Weymouth via Winchester, Southampton and Bournemouth, as well as services connecting London Waterloo and Aldershot via Woking and Guildford.

Additionally, some services between Exeter St Davids, Salisbury and London Waterloo now terminate at Basingstoke.

Exacerbating the travel chaos, services in London Waterloo are also being disrupted due to a signal failure. A report of smoke between the station and Vauxhall in the early hours of Tuesday also caused additional delays.

National Rail Surveys said services on the Elizabeth line between London Liverpool Street and Stratford were disrupted.

LNER said two speed restrictions on its routes were causing delays.

Its services are limited to 20mph on lines in St Neots, Cambridgeshire and Tollerton, North Yorkshire, where it is usually 125mph.

The operator said there were also some changes in services as Azuma has more air conditioning instead of InterCity225 trains.

Great Northern said damage to overhead power cables meant it could not operate a service between Cambridge and Kings Lynn.

The outage is expected to last until 16.30.

Overhead power lines can expand and sag in hot weather.

This results in trains having to move slower to avoid damaging the lines.

Steel rails also expand as they heat up, reaching a temperature up to 20°C higher than air temperature in direct sunlight.

Trains are being forced to run slower to reduce the chance of rail bending.

Meanwhile, the East Anglian Daily Times reported that a section of the A143 road at Stanton, near Bury St Edmunds, was melting in high temperatures.

The highway authority is applying sand and granite powder to the area to prevent further damage.

AA said that the number of breakdowns that occurred between Friday and Monday increased by 15% compared to the same period last year, due to “heat wave conditions placing extra load on vehicles”.

The company received 34,124 calls in four days, while it received 29,602 calls during the same public holiday period in 2025.

Sunday and Monday saw the biggest year-over-year increases, with a 21% increase in calls on both days, while Saturday and Friday saw increases of 17% and 5%, respectively.

AA specialist patrol Lee Morley said: “Hot weather can be particularly challenging for vehicles that already have faults, are low on coolant or have been stuck in heavy traffic for long periods.

“Overheating can escalate quickly, so drivers should not ignore warning lights, rising temperature indicators, steam, unusual odors or any change in the feel of the vehicle.

“If something doesn’t look right, it’s better to stop in a safe place and investigate rather than risk causing more damage.”