The man, in his 30's and from Essex, had spent the day walking on the mountain, but had become disorientated in the low cloud.
Using phone-find protocols, the man's position on steep ground above Llyn Cau was established, and further conversations with the walker established that he was stuck and unable to proceed.
A hasty party was dispatched to make contact with the man, but were unable to reach him with the equipment carried. As a second party brought up more technical kit, the possibility of air-support was explored, although the low cloud made this not an option.
The walker was eventually retrieved to safer ground and walked down off the mountain. Everyone was safely off the hill by 11:30 p.m.