It also warned people to take extra care as platforms may be slippery.
The Met Office has issued a yellow weather warning predicting snow and further icy conditions could be on the way this afternoon.
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The rail company warned that sleet and snow could cause disruption to services today (January 31), and said: “We advise passengers to travel earlier this evening if possible, in case of disruption caused by colder weather.”
And tomorrow (February 1), the rail operator said cold temperatures and icy conditions could cause delays.
It is set to run a number of ‘ghost trains’ to help keep the tracks clear in the early hours.
A Southern Rail spokesperson said: “The Met Office has issued several yellow weather warnings across the Govia Thameslink Railway network over the next few days.
“Trains across the Southern, Gatwick Express, Thameslink and Great Northern network are expected to run normally.
“Throughout this period of cold weather, you are advised to take extra care when boarding and alighting services, and also whilst walking around the station, as walkways and platforms may be slippery.
“Staff are proactively treating station platforms and car parks to avoid slippery surfaces, however should you come across any areas which require additional treatment, please speak to a member of station staff or get in touch with us on Twitter.”
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