The 49ers practiced under an eerie, orange sky Wednesday, as smoke and ash from fires in Northern California enveloped the Bay Area.
As strange as it looked, they would've been able to play a game amid the bizarre backdrop.
Coach Kyle Shanahan told reporters that the air quality index measured 69 during the team's walkthrough, well below the NFL's threshold of 200 that would've forced the cancellation of practice or a game.
That didn't make practicing under it any less weird, though.
"We just got back in from walkthrough and it's orange out here, too," Shanahan said (h/t ESPN's Nick Wagoner). "I feel like I'm in 'The Book of Eli' -- it's like an apocalyptic state out there."
National Weather Service meteorologist Brian Garcia told SFGate on Wednesday that the smoke will "probably not (clear up) until late in the weekend," meaning the 49ers could practice under "The Book of Eli"-esque skies for the next couple days.
But as long as the air quality doesn't significantly worsen, the 49ers will be able to play the Arizona Cardinals on Sunday at Levi's Stadium in the season opener.