More than 100 volunteers have joined the search for a man who is missing in the flood-ravaged Forbes region in central west NSW.

The 49-year-old was last seen late on Friday night at a lake near Burcher, southwest of Forbes, where his car and boat trailer, but no boat, were found.

A search began on Saturday morning involving officers from Lachlan Local Area Command, assisted by RFS and SES volunteers, helicopters, and NSW Ambulance paramedics.

A submerged boat was spotted from an aerial search of the area on Saturday afternoon, with police divers heading to the boat on Sunday to see if it’s owned by the man.

The search comes as families in nearby Condobolin and Willow Bend near Jemalong have been told to leave their homes due to the risk posed by the rising waters.