Communities across the Westcountry were last night urged to "be prepared" as the Environment Agency issued dozens of flood alerts.
Sone trains between the region and London have been cancelled because of flooding on the line near Exeter.The Met Office is forecasting up to three inches (80mm) of rain for parts of the South West, as well as South East, Midlands and North East, over the next 48 hours.
Amber warnings are in place until 4pm today.The Environment Agency has already put out several flood alerts, and said further warnings are likely to be issued for river and surface water flooding elsewhere.
"We are expecting heavy rain in the South West in the next couple of days and this might lead to some flooding," Nick Moore, from the Environment Agency, said.
"We strongly urge people to sign up to flood warnings, keep a close eye on local weather forecasts and be prepared for the possibility of flooding.
"We also ask that people stay safe, by staying away from swollen rivers and not attempting to drive through floodwater. The Environment Agency already has teams out on the ground checking on flood defences and clearing any blockages in order to reduce the risk of flooding as much as possible."
The agency warned the weather could cause significant disruption, including disruption to travel and flooding of properties and communities.
Strong winds, it said, would increase the risk of flooding with wind-blown debris potentially blocking watercourses and drains.
Yesterday afternoon flood alerts, meaning flooding is possible, were issued for the rivers Yealm, Plym, Lynher, Looe, Seaton, Tavy and Fowey. They were also issued for the Lower Tamar and rivers Torridge, Clyst, Culm, Otter, Sid, Exe, Axe, Dart and the South Devon coast.
The Environment Agency said it was likely that more serious flood warnings, meaning that flooding is expected, would be issued over the next three days.
At lunchtime yesterday the Met Office issued its own "amber" warning for rain up to 9am today. "Periods of heavy rain, including some torrential downpours, are likely to occur across parts of South West and central southern England during Sunday evening and the first part of Monday," it said.
"This will be in addition to the rain which will have fallen during the day on Sunday, such that the public should be prepared for an increased risk of both surface water and river flooding during this period."
Flood Line is on 0845 988 1188.
There have been reports of flooding across Devon this morning.Fire crews have responded to dozens of reports of flooding, mainly in a period between 6am and 10am this morning.Severe flooding was reported in the Guildhall Lane and Gramball Lane area of Wedmore due to a swollen river, with water up to 3ft deep in some properties.Flooding led to several vehicles stuck in floodwater on the A361 at Greinton, leading to the temporary closure of the road. There was also a vehicle reported stuck in floodwater on the Shurton to Hinkley Point road, Storgursey;Other locations where flooding has occurred include: Cross Lane, Axbridge; Upper New Road, Cheddar; Vole Road, Mark, Cheddar; Stawell Bridge; Greinton Bridge; Badgworth, Axbridge; Nasmith Close, Exmouth; Polsloe Road, Exeter; Musbury Road, Axminster; B3184 Farringdon; Burton Row, Brent Knoll, Highbridge; Sawyers Hill, West Buckland, Wellington; Cuck Hill, Shipham, Winscombe; Mark Causeway, Highbridge; Hillcote, Wells; Cheddon Fitzpaine; Stone Allerton; Melcombe Lane, North Petherton; Oake, Taunton; Brent Road, East Brent, Highbridge; West End, Wedmore; Turnpike Road, Axminster; Biddisham Lane, Biddisham, Badgworth; Middle Green Road, Wellington; Sparrow Hill Way, Weare, Axminster; Blackford, Wedmore; A39 Wellington; Church Street, Wedmore; Castle Street, Storgursey, Bridgwater; Turnpike Road, Lower Weare, Axbridge; Quab Lane, Wedmore; West Street, South Petherton; Rooksbridge Road, Highbridge; Meare Green, Stoke St Gregory, Ashgrove; Withy Road, East Huntspill, Highbridge; Westford, Wellington; and Middle Road, Chilton Polden, Bridgwater. Click here for the latest weather forecasts