Where you camp can make a huge difference on night time temps. Camps with south facing cliffs can radiate significant heat.
Might not be an issue in July, but I can remember nights in August that didn't drop below 90, even on the beach. We ended up sleeping in wet towels.
It is also a challenge that the terrain and micro-climate change during the trip. Camps like Deer Park and Jones Holes are almost pine & cottonwood forest, while other camps are desert rock canyons.
On one late July trip I recall needing my fleece and sleeping bag for a chilly, wet, windy overnight at the put -in, then never wearing long pants for the rest of the trip.
Here is a packing list I found on line.... I hope it helps.