I've trying to figure out what time of year will be better for a trip to Yellowstone. I haven't been there for 20 years and Mrs. Photo has never been. She got Vacation scheduled for late July and Early Sept (8-11 after labor day). The idea so far is take 3 days to get there the senic route. spend 3 days around the park. 3 days home. Here's what I'm thinking.