The Met Office has issued a severe weather warnings for rain and floods from Wednesday evening.
The highest rain totals will be in the western parts of the UK over the coming days which will be falling on very saturated ground.
Met Office Chief Forecaster, Neil Armstrong, said: “After a relatively calm day on Wednesday, wet and windy weather will move in from the west on Wednesday night.
“Low pressure will drive several days of unsettled conditions with heavy rainfall the main concern.
“We have issued a number of severe weather warnings for rain across the UK, as much as 80mm of rain could fall in some areas of the west, particularly higher ground.
“Higher ground in eastern Scotland could even see up to 100mm of rain. Our warnings are likely to be updated so keep up to date with the Met Office forecast.
“The rain will be falling on already very wet ground and where there is still lying snow in the northwest of England and parts of Scotland, snow melt will exacerbate the risk of flooding.
“It is important to check for flood warnings in your area issued by your local environment agency.”