There were major delays in Sussex this morning after flooding closed the Balcombe Tunnel. Flooding also caused queues on Sussex roads. Other parts of the South have been affected by heavy rain over night.
Network Rail engineers are currently at Balcombe Tunnel, pumping water away to allow a limited train service to begin.
Passengers are, however, being warned to check before they travel as further heavy rain is due in the area.
Two other lines remain blocked in the county, with the East Grinstead line flooded at Lingfield and Dormans and the Redhill-Tonbridge route blocked at Nuffield.
Network Rail's route managing director for Sussex, Tim Robinson said, "It has been a difficult start to the day and we apologise to passengers for their disrupted journeys today.
"We are working hard to get the lines clear again as soon as possible."
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