The stormy weather has caused a landslide on the busy commuter line through Surrey, affecting thousands of passengers.
The railway on the Redhill Line out of London, near Merstham Tunnel, is blocked after the incident at around 5.20pm today - leaving thousands of passengers facing severe delays this evening.
A spokeswoman for Southern Rail said: "It affects the line between Purley in south London and Redhill, on the way out of London.
"That is our main line coming out of London so there have been knock-on delays as a result. It is going to affect a lot of people, certainly thousands.
"The cause is weather related."
Passengers travelling along the route are being advised to either get a bus from Purley or travel down to Gatwick where they can catch an alternative train to Redhill.