My husband owes me a trip to the Grand Canyon. When we were there with the kids in July, 1976, there was a huge cloud filling the whole canyon. Couldn’t see a thing. I know that it is a deep hole in the ground because I saw it just before sundown the night before, but the day we’d planned there was a fog and rain out in the middle of summer.
My wife and I and her sister and bro-in-law from Britain were there last September. When we first started the trolley tour, the canyon was fogged out...nothing was visible. Then after about one half hour the fog lifted. My in-laws were thrilled. My wife and I have been there four or five times, but it’s still a thrill.
On your way down from Wisconsin, have him stop at Moab, UT and Bryce Canyon. If you want a thrill, take a drive on the Moki Dugway:
There is so much to see in Southern Utah/Northern Arizona, it's incredible. I suggest you stay in Kanab, UT. From there, you're within a 2 hour drive of several NPs, to include the North Rim of the Grand Canyon. Kanab is known as "Little Hollywood" as dozens of westerns have been filmed there over the past 60 years. We always stay at the Parry Lodge. It's kept in immaculate condition, and many of the most well known stars stayed there while filming their movies.
Same thing happened to me on a trip a few years ago. I still tell people I went to the GC only to find they filled it in and it’s not there anymore. The day after the train trip to the GC, we experienced all 4 seasons in one day as we left Williams AZ. It rained, tornados struck, hail fell, snow fell, and spring broke out as we went south on I-17 to Sedona. It was almost like being home in OK, just done at a higher elevation. A couple of days later, I played golf in beautiful weather in Sedona among the Red Rocks.