A second day of extreme heat has caused further disruption to Britain’s railways as two mainlines out of London closed and another was blocked by an electrical fire.
Temperatures at track level on Tuesday were expected to surpass the all-time high of 62C (144F) recorded in Suffolk on Monday. Speed restrictions were imposed across the country to slow trains down.
Rising temperatures led Network Rail and train operators to issue a “do not travel” warning for services heading north from London, with problems such as buckled rails and broken wires multiplying during the day.
Overhead lines came down in several areas, including Rugby, Birmingham and Carlisle. A number of trains were trapped, requiring emergency evacuations of passengers.
On the west coast mainline, where Avanti intercity services were initially slowed and disrupted by speed restrictions, all trains out of London Euston were eventually suspended due to a lineside fire. The blaze ignited when 25,000-volt overhead electric cables came down in Harrow, north-west London.
James Dean, Network Rail’s west coast mainline south route director, urged passengers not to travel.
He said: “Once the emergency services give us the go-ahead, we will work as fast as we can to restore the railway lines. We’re sorry to people impacted and we’re working as fast as we can to get things back up and running.”
Passenger numbers on Tuesday were down by about 40% on last week.
Network Rail decided to close the east coast mainline entirely between London, Leeds and York, stopping intercity London North Eastern Railway trains and Thameslink commuter services.
The Midland mainline between Derby, Nottingham and London was also closed from lunchtime as temperatures rose – stopping fast services to Luton airport, which reopened on Monday evening after heat-related defects closed the runway.
An escalation in infrastructure damage had been predicted after a dozen buckled rails were reported on Monday, while overhead lines were broken in two places in north-east England.
Jake Kelly, the Network Rail operations director, said it had “not taken the decision lightly” to upgrade the travel advice, adding that any journey within the Met Office’s red extreme heat warning was “going to be long, disrupted and uncomfortable”.
Most London Underground and Overground trains were running with severe delays, as parts of lines were suspended due to the heat.
Transport for London advised against all non-essential travel and warned passengers that services on Wednesday could be disrupted by possible lightning strikes and heavy rain overnight.
Drivers stayed away from city centres, with congestion levels down significantly on a week ago in London, Birmingham and Manchester during the morning peak, according to data from the navigation company TomTom.
The roads largely escaped the heatwave unscathed, with the A14 dual carriageway near Cambridge reopening on Tuesday morning after overnight repairs to a section that had buckled.
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The transport secretary, Grant Shapps, said it could take decades to upgrade existing lines to be more resilient, with the UK’s Victorian-era infrastructure “not built to withstand this type of temperature”.
He said the railways, as well as many asphalt roads, would require a “long process of replacing it and upgrading it to withstand temperatures, either very hot or sometimes much colder than we’ve been used to, and these are the impacts of global warming”.
Asked if the transport system could cope with the extreme weather, Shapps said: “The simple answer at the moment is no.”