I had a gentleman asked me this. During the afternoon during this fall the trout fishing in the lake was just super then he went out early the next day at day break the fishing was very slow and hardly any action and small fish. Well here's a part of the problem. During the cold day the temp of the water changes. It can be 49 degrees during the peak of the day then at night the water lowers 1 or 2 degrees and the fish go to deeper waters or where's there's more oxygen content and they almost stop feeding especially the bigger fish. During these cold days. Troll shallow or deep. If u don't get any action for the first 30 mins you mite be in the stage where the fish are not on the active times due to water temp.