Don't go. It's not mud. It's black soil that's deep and wet. The wind is non stop and like a hurricane. Been there twice and will never go back.

It will really just depend on the weather then. The area is wide open and exposed so unless there has been recent or a lot of rain over the preceding weeks you should be fine. A bit of rain was fine for us, (33' MH) but it can get very slippery and the mud cakes. The winds can be strong so don't leave anything, including awnings, out.

We stayed in June... so not the same timeframe as you. If it's wet it will be muddy. The road in is only ok in the best case. More concerning weather is the wind. If it's windy it will be miserable. Sorry but my opinion after one night there is I'm going to pass on it from now on.

We were there July 4 week of 2018, and it rained... very muddy. Very beautiful!!! I would go if the forecast looks close to what you want. remember that you not only have Badlands National park but also the Minute Man National Historical site.

I would just keep an eye on the weather leading up to and during your trip. It downpoured for a few hours on my last night here and the road was very hard to get out of, even jack knifed going 5-10mph. So just know the road can be messy if it's been raining. But it's a beautiful area to camp

The road is pretty good, but with heavy rains mud can be a concern. We were there June in a camper van and arrived after a heavy storm had just passed through. No wind when we arrived and we camped around 10' from the cliff face. 2 hours later incredible winds started pushing our van toward the cliff face, at least 6" of sliding on the wet roads. I started the engine and tried to drive away from the cliff face and only mnanaged about 10' before getting stuck in the mud. Next morning several other campers helped push my van out and get it going again. So mud can be a problem but there are literally hundreds of campers here to help out most any situation!