Disruption on First Great Western between London Paddington and Plymouth, between Bristol Temple Meads and Plymouth and between Westbury and Plymouth due to flooding at Tiverton Parkway.
Tickets being accepted on South West Trains and local bus services.
Service suspended between Taunton and Exeter St Davids. Some trains running Taunton-Weston Super Mare with delays of up to an hour. Passengers advised not to travel.
More top news
It will be a breezy start, with clouds arriving around lunchtime. The afternoon will be sunny with showers.
Tuesday will start dry and bright with lighter winds, before cloud thickens bringing some outbreaks of rain through the afternoon.
The day's gusts will ease as the evening goes on. It will be mostly dry with cloud cover but occasional clear spells.