The Met Office issued a severe weather warning covering most of Wales, northwest England and west Scotland for rain and flooding.
The Environment Agency issued urgent warnings for communities in Cumbria, Lancashire and Yorkshire as the heavy rainfall and gales will coincide with spring tides.
Many flood defences breached in last month's floods are still to be repaired.
The Environment Agency said it may deploy temporary barriers to reduce the flood risk to people and property.
Chris Wilding, national flood duty manager at the Environment Agency, said: "Heavy rainfall brings the risk of flooding on Tuesday and Wednesday across the southwest, Midlands, Cumbria, Lancashire and Yorkshire, with the potential for high waves along southwest and northwest coasts.
"Our thoughts are with all those who have suffered serious flooding over the past few months, and it is once again vital that people prepare for heavy rainfall and the risk of further flooding."