The light color stoneflies and mayflies are hatching so I taper down to 6X and put on a Murray's Little Yellow Stonefly Dry, Murray's Yellow Drake Dry or Light Cahill Dry size 16. I usually study the surface of the stream to see which hatch is predominate and what the trout are feeding upon and that is the fly I use.
The rain storms have been localized so some areas are receiving more rain than others. The rains have improved the trout fishing in the Shenandoah National Park but you still need to hide your approach. The trout are still wary. The water levels will be better by coming into the streams from the lower boundaries. Little Stoney Creek west of Edinburg is in good shape as well. You can access this from either the top or the lower boundary. If you need help on access to the Park, stop by the fly shop or see my book Trout Fishing in the Shenandoah National Park.