I have received the update below from Network Rail this morning which I wished to share immediately:
Extremely hot weather is expected on Thursday 25 July with temperatures forecast to reach 37°C. That means steel rail temperatures could rise to well over 50°C.
To reduce the risk of buckling and to keep passengers safe, we have to introduce speed restrictions which means fewer trains can run and they’re likely to be much busier and take longer to complete their journeys.
Our network is made of 20,000 miles of steel track, which absorbs heat easily. When steel becomes very hot it expands and if there is no room for the rail to expand further, this can cause the rail to buckle. If that happens, the line has to be closed for repair before trains can run again. You can read more about why rails buckle, here.
To avoid that scenario we introduce speed restrictions because slower trains exert less force on the track and reduce the risk of buckling.
Much like on the roads, trains can’t drive at full speed over defects and have to slow down to keep passengers safe.
• Southeastern will be running significantly fewer services that day, so please check before you travel tomorrow by clicking here.
• Thameslink and Southern will also be running a reduced service with speed restrictions in place across Sussex and Kent.
I want to ensure that we keep passengers safe and moving during this heatwave, and that is exactly what we will do with the measures that I have set out above.
Southern Region Managing Director