Fished the Middle Fork of the Snoqualmie last Friday caught more fish than I could count and the week before caught a small juvenile Dolly on a dry fly. This is by no means all the fish I caught but it's a good sample. A pic is worth a thousand words so I just shut up now.
Ya know that's what I initially thought too but I can't find any WDFW data that suggest there are any brookies in any of the three forks. I was talking with the guys at Creekside in Issaqua about it and they said it was probably a dolly. I know there were not the type of worm marks on its back that brookies have although it's hard to tell from the pics. I caught a brookie the week before in another river and there were two major differences between the two, those being the lack of black worm marks and the belly was a much lighter color than the fish in the above pic.