Of all the disruptions that can interrupt your public transport journey, perhaps hot weather is one of the stranger excuses given by rail operators.
As the hot weather ramps up and the country is basked in glorious sunshine, rail operators now have to deal with a new problem.
And here are the reasons why.
Network Rail say that in order to reduce the tracks buckling, engineers adjust the tension in the rails when they get laid so that they expand without buckling.
Train companies have to plan for hot weather (stock photo)
A spokesman for Network Rail explained: "There are some parts of our railway network that we have to take special care of when the temperature rises.
"When a rail sits in the sun all day, its temperature will rise and it will get longer. If left unchecked, that rail could buckle in the heat.
"By putting speed restrictions in place on the most vulnerable parts of our route, we can reduce the stresses on the rails and keep trains moving.
"We know this can be frustrating for passengers, and we appreciate their patience when this happens."
Furthermore, when rails are initially installed they are stretched so that they sit comfortably at the average temperatures we get in the UK.
Sun seekers lap up the weather - but it can cause problems on the rails
When those temperatures rise above normal, some areas – such as places where track has recently been worked on – can be more vulnerable to rail breaks, and speed restrictions are put in place.
Network Rail also have engineers and remote monitors to measure rail temperatures, which warn them when the temperatures get too high.
As a result, trains may be slowed down to reduce the impact on the rails which have expanded and would be at a higher risk of buckling.