Yampa is in town and has good fishing. Don't know about Casey's pond or if you can fish it.
Flows will depend on runoff so hard to say what they will be but by the end of July you should be golden. You can go to USGS and look up flows of the past to get a general idea.
Water will be chilly but I don't think it would be unbearable to wet wade, just depends if you are long legged or short legged.