I fished the upper Skagit last Thursday. The river was super low and I had to work a lot of river to get 4 fish in 5 hours. I saw only two fish rise in that time (although I did get one on a dry). I was targetting lies with nymphs mostly. the fish were holding in deep (4'+) or in riffley, highly oxygenated water. I waded sections that were chest high or better 3 weeks previously and never got in above my knees. Move around a lot and you should do OK.
I fished Sumallo grove on Sunday and it was pretty nice. The river was allot lower than when I was there in July and it made for great fishing. I was feeling lazy and only fished about 1 km of the river right from the parking lot but my laziness paid off as was able to land 6 rainbows in three hours all in the 15" to 17" range and all on dries. Once you saw a rise the water was so clear that you could easily make out the silhouette of the fish, getting to bite took a bit of trial and error. I started with my usual starter fly of a #10 Adams with big calf tail wings, this brought the trout out from their hiding spots but they would only nudge the fly or come up and follow it for a bit and then refuse the fly. I tried smaller sizes of the same pattern but it had even less effect. After checking out the bugs in the river I noticed there were a lot of mayfly nymphs so I tied on a #16 olive parachute fly which solved all my problems on my first cast. I tried different flies as I walked down but I found the parachute gave the best results. Anyways that’s my story and I'm sticking to it. As for getting there follow the #1 to Hope get on the #3 to Manning park follow it for around 20mins and watch for the signs Sumallo Grove.