Thanks Pacific. I guess my "Break Glass in case of Emergency" option is to cancel our last couple of nights at YVL (we have Mon-Fri booked) if it is too hot to hike and go to San Fran early where we are flying out of.

Anyone have thoughts on Muir Woods? Always wanted to get to Redwoods NP someday but it didn't look to be in the cards logistically. Are the redwoods at Muir of a similar age/size? This would seem like a decent alternative if needed. At least for one day.

Ask on the state forum for alternative ideas or consider the SF (not SanFran) forum or Santa Cruz forum (Henry Cowell Redwoods)

I would stay in Yosemite, but your family may need cooler tourism options.

Sorry the forecast is for such high temps next week. That can put a damper on things especially since you are such avid hikers. Just reading the google reviews for The Yosemite Conservation Heritage Center and it looks like a very interesting historic structure--sorry we missed it! Do note they are closed on Monday and Tuesday.

Muir Woods is beautiful, btw. We've been twice.

I would look at 2-3 nights in Yosemite Valley and 1-2 nights in Lee Vining, June or Mammoth Lakes- do higher elevation hikes along Tioga rd and the eastern Sierra.

Hi there, what do you mean "rafting is done"? Can we no longer rent rafts to float the river? I know it's a short season but though at least through mid July. ? no?

Raft rentals are closed for the season. Drought. You can put you own rafts in which can be bought at most drugstores, like cvs or RiteAid. https://www.travelyosemite.com/things-to-do/rafting/

Where are you seeing a heatwave expected? My 10 day forecast has a few 88 degree days which is pretty common in July.

LemonCurls has a good suggestion to look at the Eastern Sierra where temps are expected to be lower (80s in Mammoth Lakes as opposed to 90s in Yosemite Village).

Take a look at Reds Meadow, Devils Postpile, June Lake and Mammoth Mountain to see if they are attractive. You can combine a stay with hikes in cooler Tuolumne Meadows on the way. At the very least, lots of AirBnB and hotels with air conditioning - unlike YVL.

We spent some time swimming in the river right behind YVL when it was sweltering last year.

There is a little theatre just behind and connected with the Visitor Center, which shows short overview/introduction to Yosemite films every 1/2 hour or so (very informal, can enter or leave anytime). It felt like the A/C was on, but honestly it was rather weak. Not the kind you wonderful cold blast you feel in a full size movie theatre or large grocery store. Still, it was better than nothing (we had 3 days at 85-86 degrees in May, and I can't imagine enjoying the park any hotter than that, but everyone has a different level of tolerance). The fan in our room helped, but it remained warmish even with this.

I've been in Yosemite in July when the valley temperatures are in the 90s. That's an ideal time to head for the high country where it is cooler. My husband and I did the Cathedral Likes ( https://www.yosemitehikes.com/tioga-road/cathedral-lakes/cathedral-lakes.htm ) hike one day when the valley was very hot. You might also consider Elizabeth Lake ( https://www.yosemitehikes.com/tioga-road/elizabeth-lake/elizabeth-lake.htm ) which, from memory, is mostly shaded.

The Gaylor Lakes ( https://www.yosemitehikes.com/tioga-road/gaylor-lakes/gaylor-lakes.htm ) trail starts near the Tioga Pass entrance and then climbs up and over the ridge, but it will be cooler up there than in the valley. If these all sound a bit much, you might take your swimming costumes and cool off in Tenaya Lake.