Key Takeaways June is peak season at Zion: hot, sunny, and busy. Canyon highs climb from about 87°F at the start of the month to 97°F by month's end, and on the hottest days the main canyon can exceed 100°F. The Narrows is at its prime in June. By now snowmelt has dropped and the water has warmed, the bottom-up hike from Temple of Sinawava needs no permit, and it stays open unless flow tops 150 CFS or a Flash Flood Warning is issued. Angels Landing is open but requires a permit beyond Scout Lookout. The chains section is reservation-only; you can hike to Scout Lookout via the West Rim Trail with no permit. The Zion Canyon Scenic Drive is closed to private vehicles all month. Access is by the free, no-reservation shuttle (on its summer schedule, May 17-Sept 12), so plan your day around it and arrive early. Heat, dehydration, and flash floods are the season's real hazards. Carry about a gallon of water per person per day, start strenuous hikes before 8 a.m., and never enter a slot canyon when storms threaten. A guided Four Season Guides trip handles permits, logistics, and route planning so you can focus on the hiking.
Visiting Sedona in June: low-90s heat, fewer crowds than spring, the monsoon's onset, the free shuttle, and dawn-start tips for hiking the red rocks.