Wading in Yellowstone

[bias5246]

I'm planning a trip in Yellowstone for late July. I think we'll be fishing the Lamar, Slough, and maybe a few surrounding streams. I've never been out west, and was wondering how cold the water will be that time of year. Can I wear wet wading sandals, will I need neoprene booties with them? Or will I need waders?

Also, given the lack of snowfall, does anyone know how significant an impact this could have on the Northeast section of the park?