No magic tactic or fly in the winter, but to sum it up fish….."low and slow."
I generally use small generic nymphs like the BHHR size 16-18. In mid-winter / early spring I will use tiny black stonefly nymphs if I see them along the banks or know they are present in the stream. On rare occasions trout rise to drifting stoneflies in the winter and I use dry flies. I don’t like fishing streamers much, but sometimes a drifting or slowly retrieved bugger saves the day.
I fish nymphs very close to the bottom. I cover every inch the water very slowly and carefully since trout in the winter won’t travel very far for a fly. I find most fish in the slower deeper water in the winter.
I use midges if fish are rising, but find tiny midge pupa fished just under the surface to be most effective. The best midge pupa patterns I’ve found are tiny bead head thread midges in the appropriate color tied on pupa/scud hooks (like TMC 2487 or 2457). When you put a bead on them they ride hook point up like a natural pupa. I use 1.5mm beads. When fishing midges I use a small but visible dry as a strike indicator in rippled water, or in flatter water I use a small pinch of strike putty on the tippet knot to track the tippet. In a glassy water, like near the dam at the Yellow Breeches, you can “grease” all but the last foot of your leader and tippet and just watch your tippet.
In the winter, no need to get up early, the best time to fish is usually mid afternoon, when the water is warmest. I have noticed that during a warm spell with snow on the ground, the water temperature actually goes down due to the snow melt. I still catch some fish, but I usually don’t have a great day fishing when the water temp is below 40*. The fishing usually improves at 40+.
I look forward to fishing this winter. Good luck – stay warm.