As of Sept 1, the wind has shifted and heavy smoke is now clogging the previously unaffected Yosemite Valley. Visitors report being unable to even see the cliff walls from Valley campsites. A friend who was camped clear up on the Glacier Point Road in the Bridalveil Creek Campground until yesterday pulled up stakes and headed to the coast to finish his family's vacation because of heavy smoke.
Several FT users have reported plans to visit Yosemite this fall and several of us have recommended a stop at Yosemite for international visitors to California. At this point, I have to change my recommendation and suggest making alternate plans. The Tioga Pass Highway is closed, Yosemite Valley is obscured with smoke and even the higher Glacier Point Road is unpleasantly smokey. The fire is expected to continue to burn until the autumn storms start up.
For visitors to California who wish to see the Sierra Nevada Mountains, I would suggest a visit to Sequoia and Kings Canyon National Parks to the south.