It was Sunday afternoon and the Arco gas station was buzzing.

Four lowriders, parked alongside gas pumps, gleamed in the afternoon sun in Altadena. Carne asada sizzled on a grill at a pop-up taco stand in the corner. A group of old friends sat on camping chairs and passed around a freshly rolled blunt, cracking jokes and showing each other photos on their phones. Hip-hop played on a wireless speaker.

This is not what a disaster scene is supposed to look like.

Yet somehow this filling station, perched across the street from one of the most destructive wildfires in California’s history, had suddenly become the vibrant hub of a traumatized neighborhood, a harbor for residents desperate for food, clothes and, especially, community.

The Arco station, otherwise known for cheap fuel, could no longer serve its primary purpose once the Santa Ana winds bore down on the neighborhood on Jan. 7 and knocked out its power. What it had instead was proximity to the fire zone and the ingenuity of locals.

Just feet from the taco stand were a dozen tables piled with donated shirts, blankets and toiletries that were meticulously organized. A moving van loaded with cases of water, boxes of chips and crates of diapers backed into the gas station.

And in the center of it all stood Jorge Trujillo, who had helped to build a full-fledged relief operation overnight.

“Nothing was planned,” Mr. Trujillo, 37, said as he watched the scene. “Everyone just gravitated here.”