Parts of the UK are braced for threatened further flooding as successive bands of heavy rain move across the country.

The Environment Agency (EA) said large swathes of southern and south-western England, south-east Wales and the Midlands were potentially under threat. Flood warnings, which suggest flooding is expected, are in place in the South West, the South East and East Anglia, said the EA.

River levels on the River Cober in Helston, Cornwall, are high after persistent rain on Wednesday, while the Dolphins River Park in Charmouth, west Dorset, is under threat from the River Char. The River Wey in Weymouth, Dorset, is rising and the Somerset Levels also face risk of flooding due to heavy rainfall of up to 20mm over last night on already saturated ground.

Forecasters said the heavy rain would ease off in the South West later and it would be dry on Friday, but warned the weather across the whole country is likely to remain unsettled for up to seven days.

Andy Ratcliffe, a forecaster for MeteoGroup, the weather division of the Press Association, said: "There will be persistent rain across most of the UK today, though in the South West it will turn drier in the afternoon with the odd shower. (On Friday) it will largely be dry in the South West, but by the evening the next band of rain will move in. That will stay throughout the weekend and into next week."

With the possibility of more flooding on the way, people are being urged to keep up to date with the latest information from the EA's website, sign up to free flood warnings, check their route for disruption before travelling, and not to drive or walk through floodwater.

Darron Burness, the AA's head of special operations, said: "Unfortunately, following this morning, some drivers will be asking Santa for a new car after driving down flooded roads. It's just not worth the risk, so stay out of floodwater, as it can hide all manner of hazards and you seriously risk wrecking your engine or worse."

Craig Woolhouse, flood risk manager at the Environment Agency, said: "Our teams are out around the clock to minimise the risks and prepare for flooding, clearing drainage channels and ensuring that flood defences are working properly. We urge people to keep up to date with the weather forecast and local news overnight and remain prepared for flooding in their area by signing up to receive free flood warnings and staying away from dangerous flood water."

The Environment Agency in the Midlands said almost 56 flood alerts are currently in place, with one flood warning issued for the River Frome near Stroud in Gloucestershire. In the riverside town of Bewdley in Worcestershire, on the banks of the Severn, flood defences were being put up, and at Upton-upon-Severn existing flood barriers were being monitored with the river predicted to keep rising. Defences are also set to go up in Shrewsbury, Shropshire.

Hampshire Fire and Rescue Service said it had rescued six people stuck in their vehicles after driving into floodwater in Fareham, Brockenhurst, Ringwood, Wallington and Waterlooville. In the Brockenhurst incident, a man and his daughter were pulled from their Porsche when it became submerged in a ford. They were helped by a police community support officer after they swam from the car.