So with a trip to Yellowstone for the family looming now about 5 months away (last week of June) I need to start buying and/or tying flies for that area and its rivers. I've started compiling some lists from local guide sites and that has been very productive. What I ask the collective, those of you who have fished this amazing place, what are your must have flies for the late June, early July time frame? I realize that depending on temps, winter's weather and snowpack and how fast those temps change that run off could be done or it could be high. Fishing is not the priority, the family enjoying the trip and park is. As such, any tips on what might get noticed and slurped or struck would be appreciated.