I fish in exactly the same conditions but no weeds.

Nymphs and streamers seem to do the trick.

Pheasant tail will work on stocked fish regardles of the season second choice would be Muddler minnow. Beadhead emergers are my go to fly - I carry 5 different colors.

If the water is cold the trick is very slow retrive but don't be afaraid to experiment. I had caught fish in very cold water by using small flashy streames when they would not even look ant nymphs.