I had a season pass to MW last year and went a lot during the summer and it was always open. It was closed for an occasional hour or two here and there but that happens with a lot of rides. I have seen it run two trains but that was on one Saturday when the park was very crowded. I noticed they rotated which trains were in operation also, sometimes purple, sometimes red, or sometimes blue. I haven't gone this season yet but I will in the next couple of weeks and see how Zonga is (weather if its open or not, I most likely will never ride again)