- "At 9:45, Doc Brown began to grow apprehensive. Five minutes later, he was definitely in a nervous state. By 9:55, he was pacing wildly back and forth. / "Damn!" he muttered. "Where is that kid?" / His trenchcoat was whipping loudly in the wind, like the spinnaker of a sailboat caught in a storm. The distant thunder now rumbled sullenly all about him, punctuated by sharp flashes of lightning illuminating the outline of his tower-to-lamp-post cable network. Town Square was deserted except for a small pack of dogs and he was ready to go. But no Marty."
- —From Back to the Future by George Gipe (quote, page 225)
- " Doc reached into the toolbox. He handed his 1955 version the correct wrench without turning around. But should he say something else? Maybe a little polite conversation would keep his younger self from getting suspicious. / 'I presume,' Doc added, 'you're conducting some sort of weather experiment.' / 'That's right!' 1955 exclaimed, every bit as astonished as before [when Doc corrected 1955's request for a ⅜ inch wrench to a ½ inch]. 'How did you know that?' / 'Oh,' Doc replied humbly (but still as gruffly as his [disguised] voice could stand), 'I happen to have a little experience in that area.' / 'Yes, well,' 1955 exclaimed, pleased to find a colleague. 'I'm hoping to see some lightning tonight, although the weatherman says there's not going to be any rain.' / 'Oh,' Doc reassured him, 'there'll be rain all right. And wind, thunder, lightning—' He couldn't help but chuckle. 'It's gonna be one hell of a storm.' / He heard the rustle of the tarp as his 1955 self prepared to go back into the car. / 'Well, nice talking to you,' 1955 said. 'Maybe we'll bump into each other again in the future.' / 'Or the past,' Doc added, once his younger self was gone and he was safely back on his bike. "
- —From Back to the Future Part II novelization by Craig Shaw Gardner (quote, page 164)
The Hill Valley Thunderstorm was a highly electrical severe thunderstorm that hit Hill Valley, California on the night of November 12, 1955, the same night as the local Enchantment Under the Sea dance at Hill Valley High School. At precisely 10:04:00 p.m., lightning struck the clock tower of the Hill Valley Courthouse, freezing the clock at that time for at least sixty years. Numerous attempts were made to replace the clock tower after the incident, but the Hill Valley Preservation Society intervened and collected donations to keep it standing.
Originally thought to be a clear night, the weather forecast for the area changed dramatically about one hour prior to the storm's arrival and a severe thunderstorm warning for Hill Valley was issued on the radio. The storm was powerful enough to take down several trees around the Hill Valley area, including a large one split by lightning at the construction site of Lyon Estates two miles from town.
Marty McFly and Doc Brown used the storm as a way to channel electricity, 1.21 gigawatts of it, into the DeLorean time machine's flux capacitor, rendering the vehicle capable of entering temporal displacement and allowing Marty to return to 1985. Doc came up with an ingenious plan to rig a cable to the clock tower and string it over the street where the DeLorean would intersect it.
When Doc and Marty returned to 1955 to retrieve the Grays Sports Almanac, they encountered the storm at Lyon Estates before it reached town. Lightning struck the flying DeLorean, sending Doc back to 1885. After the violent bursts of lightning ended, there came a large downpour of rain, through which a man from Western Union drove to give Marty Doc's letter.
Significance of the storm in time travel
When Marty found another DeLorean parked outside Doc's garage in 1986, it was unclear exactly how another time machine had come to be. An imprisoned Doc in 1931 explained to Marty that on the night of the Hill Valley Thunderstorm, the moment the car was sent back to the future, a temporal duplicate of the DeLorean was created and sent forward seventy years to 2025. It is unclear whether this was due to a malfunction with the time circuits, or an substantial side effect of time travel.
- Back to the Future trilogy
- Back to the Future: The Animated Series
- "Go Fly a Kite" (Trilogy footage in the live action segment)
- Back to the Future: The Game (Mentioned only)