Many photographers know the Sunny-16 Rule: a sunny mid-day exposure is f/16 at a shutter speed of 1/ISO. For example, f/16 at 1/200 second at ISO 200. Now I propose the Smoky-16 Rule, which estimates the daylight exposure in the vicinity of an unprecedented wildfire, like the kinds we're now experiencing in California. Our fires were ignited during a heat wave that reached 130F (54.4C) and dry thunderstorms that brought 12,000 lightning strikes but no rain. I took the photo below at high noon today (September 9, 2020) from my third-floor balcony near San Francisco. The Sunny-16 exposure should be 1/800 second at f/16 at ISO 800. Instead, my metered exposure was 1/42 second at f/2 at ISO 800. So, my Smoky-16 exposure is Sunny-16 plus 10 stops -- a difference of about 1,000 percent. My camera's auto white balance doesn't fully capture the weird orange glow of this noontime pseudo-daylight, which a friend describes as "Martian." Cars are driving with their headlights, and indoors we've got all the lights on. I slept until 8:30 this morning because I didn't know it was daytime. As I write this at 3 p.m. the same afternoon, it's a few stops darker now. So dark that a sharp handheld exposure at f/2 and ISO 800 isn't possible, even with my camera's motion stabilization. I'd need a tripod to make a time exposure. Australia suffered similar wildfires earlier this year, reportedly killing one billion animals. Now it's our turn. Unprecedented fires have also burned above the Arctic Circle in Sweden and Siberia. I'm afraid my Smoky-16 Rule has a bright future.