When is the best time to plan a family vacation to the Zion National Park??

We were just there and it was not crowded at all. We got up early and were at the park at 6am both days and the weather was great. In the afternoons it was in the mid 90s but coming from AZ it didn't bother us.

I would go now while the park is much less crowded. The only caveat to that is if you are HARD CORE and want to hike every available trail, some are currently closed. If you want to see many sites, know you won't have time to see it all, then now is the PERFECT time to go. You'll never see it less crowded.

It has been less busy than usual both times we have gone this summer, but honestly it is so hot. I would say if you can go in late September/October you might be better off.

Was there last week! Great time to go, just need to get your shuttle tickets.