The Met Office has issued rain warnings for most of Wales and parts of England from Wednesday evening to Thursday morning, with wet weather predicted to continue until at least Saturday.
After early showers in northern, western and central parts of the country on Wednesday, areas of rain will be largely confined to the Highlands and the far north of Scotland until the late afternoon.
Alex Deakin, a meteorologist at the Met Office, said that the weather elsewhere will be good for many people on Wednesday.
Comparing conditions to those earlier this week, he said: “It’s sunshine and showers again but not as many showers. In fact, many places will have a dry, fine day on Wednesday.”
However, a large band of cloud and rain will push into the UK from the south-west, reaching Cornwall and Devon by “tea time” and then spreading across England, Wales and perhaps Northern Ireland during Wednesday night.
“It could be quite heavy in places and after such a wet spell over the weekend, we do need to watch this area of rain,” Mr Deakin said, referring to Storm Alex, which brought a month’s worth of rain to the UK over the period of few days.
As a result of this patch of weather, the Met Office issued yellow weather warnings for rain for much of Wales and parts of central and northern England from 9pm on Wednesday to 9am on Thursday due to possible flooding and travel disruptions.
Forecasters do not know how far north the band of low pressure will travel and how quickly it will clear but said it would remain until Thursday.
More showers are expected on Friday and Saturday, before a new weather front sweeps into the UK bringing brighter weather.
Temperatures throughout the week will stay on the cooler side, with the temperature hovering around 13C for many places on Wednesday.