You know it probably will.
Every year, weather forecasters around the Bay Area try to be really optimistic about what the fog is going to look like after sundown on the 4th of July, when people across the city will be angling to see at least one firework from wherever they're standing. Some years, the fog rolls in so thickly that even if you're right on top of the fireworks display at the Embarcadero/Fisherman's Wharf, the upper parts of the glowing starbursts get obscured. That is probably going to happen again this year.
Depending on who you trust, temperatures in the city on Friday are going to top out around 64 or 67 degrees, with fog rolling in probably well before sundown. Lows tomorrow night will be around 53 degrees.
As ABC 7's Leyla Gulen shows us on the big map, San Francisco should be pretty well engulfed by sunset on the 4th, at 8:35 p.m., so don't expect to see anything but the faintest glimmers of the official fireworks display from anywhere except the Embarcadero.
If you want to see fireworks in the clear, you're best headed to Sonoma, Livermore, Danville, or the South Bay. (Even Oakland looks like it'll be in the fog path.) Or you could just chill in the Mission and watch the illegal ones go off in every direction, from every other rooftop and alley.
Once again, be careful out there!