mdrski,
Welcome to the Paff forums. It's mostly a trout fishing crew here - not a lot of warm water folks much less those who fish large lakes. With that said, we do have a lot of folks in western PA who hopefully will chime in. I don't fish Pymatuning myself so take my advice as general info. Pymatuning is a world class muskie lake and good for bass and walleyes. Wading it with a fly rod this time of year would, I would think, be tough fishing. I'd recommend hitting the lake shore early in the am and evening. Fish a popper to any obvious cover - blow down trees, weed edges etc. If this fails, try a streamer a bit deeper. If this too fails to stick a bass or two.....I'd tie on some small nymphs and fish 'em under a floating strike indicator (basically a bobber) and catch some bluegills.