With temperatures set to reach as high as 35C during the heatwave in Britain this week, rail passengers are being warned the hot weather could bring travel chaos.
Network Rail says it will be forced impose speed restrictions on certain services in a bid to prevent its train tracks from 'buckling', as steel rails expand in the heat. In direct sunshine, steel rails can reach as much as 20 degrees centigrade above air temperature.
On its website, a statement from Network Rail says: " "When we install track, small gaps – called expansion joints – are left between sections of steel rails to safely allow a small amount of expansion during hot weather. If the joints have already fully closed up and the rail continues to expand, then the rail starts to go into what is known as 'compression'.
"In extreme cases the tracks can buckle, making it impossible to run trains.
"Usually, these repairs can't be done until the temperature of the rails has dropped, causing significant disruption for passengers and freight. That's why it's so important that we take precautionary steps to stop this from happening.
A Network Rail spokesperson added: "Track temperatures this week are predicted to exceed 50 degrees Celsius in many places, meaning we will need to impose speed restrictions at some locations. This is because slower trains exert lower forces on the track, reducing the risk of buckling and keeping passengers moving."
So what exactly can we expect from this week's weather? Leon Brown, meteorologist at The Weather Channel, told Aol Travel: "Temperatures could reach near record levels on Wednesday.
"The high temperatures are with us until Saturday, but at the moment this Wednesday looks set to be the hottest day.
"The heat will kick off some thunderstorms, especially over northern Britain on Wednesday evening with flash flooding possible and then again on Friday evening over eastern England.
"Tuesday will be clear and sunny across England and Wales with temperatures reaching 28C to 29C over central England and around 30C to possibly 31C in the south.
"Scotland is warming up but not as hot as the south, reaching 24C to 25C.
"Wednesday will be very hot across England and Wales with temperatures between 28C to 31C in Wales, 31C to possibly 33C over central England and even hotter over the south east where 34C to 35C are possible.
"The 1 July record is 34.8C in Jersey back in 1952 and 33.9C at a number of mainland locations in south east England in 1976 which is likely to be broken. In Scotland 28C looks likely in the south and 27C around Inverness.
"Thursday temperatures will be a little lower, and there will be a risk of scattered thunderstorms in the morning crossing the south, but even so temperatures will widely be in the mid-20s and 29C in eastern England.
"Friday will be another hot and sunny day with 32C likely in the London area and 28C to 30C across the Midlands to East Anglia. Scattered evening thunderstorms are likely over the south and east.
"On Saturday, the west will begin to cool down as a cold front moves eastwards from the Atlantic, but central and eastern Britain may still be hot with temperatures in the high 20s to over 30C in the south east.
"Sunday will be fresher everywhere with temperatures in the 20C to 24C range with fine and mostly sunny weather over the south and isolated showers over Scotland.
"Next week the south may again see a hot start with temperatures over 30C before it cools down to nearer average."
At last. Time to break out the BBQ.
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