Frequently the last two hours of the day at this time of the year you can put on a Murray's Sulphur Dry size 16 and catch several trout in each pool. Fish the tail of the pool first and release these trout gently and the trout in the head of the pool will still take your fly. Another great fly to use this month is the Murray's Flying Beetle in size 14 or 16. I have switched to 6X leaders.
All of the streams in the Shenandoah National Park are clear and fishable. Some of them are getting a little low so make sure you hide your approach even if you have to go to your hands and knees so that you are not spooking the trout.