Yellowstone Questions

KOA's vary widely in their amenities. If you have kids, sometimes the hookups and pool make all the difference in the world. They also tend to be family friendly. Not all privately owned parks are for kids. Depending on your destination, a private park might be your best option. But look into county/state/national parks if they're available. Yellowstone's parks are worth the stay if you can get one.

What does "KOA" stand for? We are also looking to go and would like to stay in the park.

Yes, Yellowstone gets cold in September. The earlier in September you go the better. With any national park, we always try to go as late in the season as possible to avoid the crowds. Anytime after Labor Day is pretty good in Wyoming, mainly because it starts to get chilly.    

PanamaMitch is quite right.  Gonna be chilly nights. You'll see lots of wildlife as the animals are migrating down from the higher country. Not sure when the Elk Refugee begins to fill though like Yellowstone the Tetons will be awesome. 

The best way to see Yellowstone is from within. There are a lot of wonderful campgrounds, but many are first-come-first-serve. Making reservations would be best. Going online is the best way to gain information. Plan to pick two or three as your base camp throughout your stay (remember, the park is huge and speed limits slow). If you don't want to rough it, the KOA in Cody is about one hour from the east entrance. It's a beautiful KOA, and the Buffalo Bill Center of the West in Cody is a must see (you can easily spend two days just in the museum). There's a KOA right outside of Jackson (about 15 minutes to Jackson and then another hour or more to Grand Teton and then to the south entrance to Yellowstone - our favorite entrance). This KOA is right on the Snake River, and Jackson is another place you could spend a day or two. Staying at either of the KOAs I mention would put a real burden on you as far as using them as a base camp - way too much travel time to and from (and traffic can be bad). What it all boils down to is how many days you will actually be in the park and which direction you'll be entering. Try to stay inside and see it all. Being from Wyoming we're very proud of our beautiful treasure! You'll love it.