I'm very excited about the heavy sulphur mayfly hatch that has already started. The duns start coming off about noon and continue until dark. The spinners start returning at dusk and continue until dark. My favorite flies are Murray's Sulphur Dry size 16 & 18, Shenk's Sulphur Dry size 16 & 18. Fish these on a Classic 9ft 6X leader except in the small mountain trout streams, then use a Murray's 6ft Mountain Trout Leader in a 6X.
The recent rains have kept these streams in wonderful conditions. The Shenandoah National Park as reopened their boundary access on all streams and of course the Skyline Drive is open for upper access on the streams. For more information on these streams, be sure to check out my book, Trout Fishing in the Shenandoah National Park.