The search for 71 year old John Concannon resumes tomorrow, with a foot search of an area close to the spot where John was seen on CCTV getting off a bus in November.
John's family are appeal for volunteers to participate, gathering in Bridgend at midday.
The latest coordinated search will begin tomorrow, with people meeting up in the back car park of the Blackthorn Amusement Arcade in Bridgend.
Searchers will be split into groups, and a miniibus has been arranged to bring each group to its drop off point and collect them again once the search is completed.
In light of recent weather conditions, volunteers are being urged to wear suitable waterproof clothing, and a good pair of sturdy waterproof boots. High-Vis vests are also recommended.
John Concannon, who has dementia and hearing difficulties, disappeared after apparently getting on the wrong bus at the Foyle Street Bus Station in Derry on November 10th.
The last sighting of him is on CCTV footage showing him getting off the bus on the Leenamore Road, close to the Donegal border.