As the UK melts in unprecedented temperatures, the Met Office issued its first-ever Red Weather Warning for exceptional heat. With that brings a whole lot of chaos, including train cancellations. The reason? Extreme temperatures, reaching 38°C+ (100°F), can cause steel tracks to buckle, grinding Britain's public transport network to a halt. A spokesperson for Network Rail says: "Rails in direct sunshine can be as much as 26°C (36°F) hotter than air temperature." The steel then expands and starts to curve, known as buckling. Given Britain's railways cover 20,000 miles (32,000km) of steel track, it's no wonder there are cancellations throughout the country.