National Resources Wales have issued the red alert for the lower Dee Valley from Llangollen to south of Chester.
It says river levels are above normal but flooding of property is not expected at the moment.
"There is a significant risk of localised flooding problems from surface water," a spokesman said.
The village was flooded in January when Storm Christoph swept across the UK.
A lesser flood alert is in force for the Upper Dee above and through Llangollen.
In Shropshire flood alerts are in place for the River Severn in Shropshire, the Severn Vyrnwy confluence and the Tern and Perry catchments in the north of the county.
Heavy rain for Shropshire today is expected to give way to sunshine and showers on Monday, drying up from Wednesday.