Large parts of the UK are likely to be hit by heavy downpours this week, with some covered by flood warnings.
The worst-affected regions could see up to 70mm of rain over 48 hours.
It comes after a weekend which saw up to eight centimetres of snow in parts of eastern England.
There is an amber warning for rain covering a circular area including Sheffield, Manchester, Blackburn and Leeds from 6am on Tuesday until the end of Wednesday.
The Met Office warning says heavy rainfall should be expected which, combined with some melting snow across the hills, is likely to lead to some flooding.
Buildings are likely be damaged, floodwater could cause "danger to life", and travel is likely to be difficult.
Watch: COVID-19 - Fresh weather warnings after snow forces coronavirus testing centres to close
There is also a yellow, less severe, warning for rain for Tuesday, covering a much larger area including Wales, and the top half of England. On Wednesday and Thursday, this warning expands to cover all of England and Wales.
Parts of Wales could see up to 200mm of rain over the period.
John Griffiths, a Met Office forecaster, said: "An area of low pressure will move in late on Monday, bringing with it quite a lot of rain over the following three days.
"Between Tuesday and Wednesday around 40-70 mm of rainfall is expected to fall in the north-west of England, potentially rising to 100-120mm in the hilly areas.
"On Thursday more deep low pressure will start travelling south to the rest of England, with strong downpours and heavy gales coming in from the North Sea."
The Environment Agency had 14 flood warnings in place across England on Sunday evening, stretching from the South East to the North East, meaning "immediate action" is required.
Natural Resources Wales said there was a very low flood risk on Monday and a low risk on Tuesday, Wednesday and Thursday, meaning flooding is possible.
Watch: What you can and can't do during England's third national lockdown