Pyro Spectaculars, the California-based company behind the display, is preparing thousands of pyrotechnic devices for Saturday night's show, commemorating America's 250th birthday, including fireworks that will launch from barges on the bay and from the Golden Gate Bridge itself.
The company says the show is designed with San Francisco weather in mind.
"It's always possible we're going to get fog when we're shooting fireworks in San Francisco," said Monty Gill, crew lead for the San Francisco show.
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Gill said the display has been built in layers, with fireworks at different heights so people still have a chance to see the show even if fog rolls in.
"There's going to be low-level (fireworks), as low as 75 feet and as high as 1,200 feet," Gill said. He also says fireworks technology has advanced greatly in recent years, becoming safer and brighter.
Crews were working this week near Mission Bay, where the barge portion of the show is being assembled. Gill said the two barges for San Francisco will each carry about 1,500 pyrotechnic devices. More than 5,000 additional devices will be placed on the Golden Gate Bridge. One barge will be placed near Fort Mason and another closer to Pier 39.
This will be only the third time fireworks have been fired from the bridge, according to Gill. Pyro Spectaculars says it has been behind each Golden Gate Bridge fireworks display. The fireworks on the bridge have already been prepared and installed, Gill said. They will fire from each layer of the bridge towers and along the east side rail.
The San Francisco show will be digitized and timed by computer, allowing the fireworks from the barges and the bridge to be choreographed together.
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The work is part of a larger national effort by Pyro Spectaculars for America's 250th birthday. The company says it is producing more than 300 shows across the country this Fourth of July holiday, from coast to coast.
In the Bay Area, the preparation also includes several other shows. Matt Boom, a licensed operator for Pyro Spectaculars, is helping run the Richmond Marina show Friday night using a more old-fashioned pin board system.
"It allows me to pace everything the way I would like it," Boom said. "I can listen to the crowd. I can speed it up."
The San Francisco fireworks show is scheduled to begin at 9:30 p.m. Saturday. Crews say the best views will be from areas with a clear look toward the bridge and northern waterfront, including Crissy Field, the Marina and Pier 39.
The show is expected to last 15 minutes.