Yellowstone/Grand Tetons in September 2014

We were at Yellowstone 2 years ago at the end of September. We weren't camping, we didn't get a camper until this year (the accomodations in West Yellowstone might have contributed to that decision. Clean, but spartan). Beautiful time of year if the weather cooperates. It was perfect for us - the two days we toured the park, it was 25 degrees when we got up, and in the 70's by early afternoon, clear sunshine both days. It was mating season for the Elk, so they were very active. We were there the 21-23rd, and the tourists were pretty thin by that time.
Of course, two days after we left, they got their first snow of the season, 10"........ Timing and luck are everything!
Mark