anywhere with a high glacier
tignes, saas fee , 2 alpes are some examples
I would actually advise strongly against the tignes summer park. in my experience the park up on the glacier sucks balls. it might well be that they put together a decent one this year though, given how sick the winter valpark has got lately, mostly thanks to coreUPT being in tignes. I would wait for some sort of official confirmation that they're planning to step it up in tignes this summer, coz if not, there are waaaaay better places. les 2 alpes has a killer summer park but hune or early july is much better than august when snowmelt becomes a major issue. saas fee can be good too, and zermatt has a great pipe.
there might be good parks at kaunertal, hintertux or les diablerets i can't remember if they open in the summer or just autumn. i believe there's a couple of good glacier parks in italy that are way under the radar but really good parks. pm michael_bc, he knows more than most.