The Prince of Wales will visit St Asaph on Monday to offer his support to flood victims and thank members of the emergency services.
The city was submerged on Tuesday when the River Elwy burst its banks following days of persistent rain.
Hundreds of properties were affected and many families have been forced out of their homes as Christmas approaches.
A spokeswoman for Clarence House said: "Following the terrible floods across areas of the United Kingdom in the past few days, The Prince of Wales is keen to thank emergency services and lend his support to some of the residents affected.
"The Prince decided to visit St Asaph because the city has been particularly badly hit by the flooding, with over 180 homes in St Asaph affected."