The city was still shrouded in early morning darkness when something deeper and more ominous than a passing thunderstorm rippled across South and Southwest Philadelphia, driving people out of their beds.

One by one, residents darted to their windows and front steps, wondering if they’d discover some mundane explanation — a ruptured gas main, a blown transformer, an especially bad car wreck.

What they found was an apocalyptic vision.

“I could see it from my bedroom window,” said Matthew Terranova, 42. “Something that looked almost like a nuclear disaster.”

Updated locator map of the refinery explosion on June 21, 2019, at the Philadelphia Energy Solutions refinery in South Philadelphia

Terranova, an Amazon worker, was peering from his house at 28th and Porter Streets at the nearby Philadelphia Energy Solutions refinery, which was rocked by a series of powerful explosions about 4 a.m. Friday.

Passing motorists soon began sharing footage on social media of the blasts, which briefly obscured the refinery — a longtime source of controversy and concern for local residents and environmental activists — in a wall of fire.

The first explosion triggered car alarms in Jeanne Fortuna’s neighborhood, the Reserve at Packer Park. A second, louder one gave way to an unnerving scene. “The sky was orange,” said Fortuna, 55, “and a giant flame shot up in the air.”

Flames and smoke emerge from the Philadelphia Energy Solutions Refining Complex in Philadelphia, Friday, June 21, 2019.
Matt Rourke / AP

Flames and smoke emerge from the Philadelphia Energy Solutions Refining Complex in Philadelphia, Friday, June 21, 2019.

So intense was the blaze that it showed up on satellite infrared images, according to the National Weather Service’s Key West, Fla., office. It left five people with minor injuries.

For some, the three-alarm fire and subsequent shelter-in-place messages from the city felt like the arrival of a nightmare they’ve feared for years. The oil refinery is the largest on the East Coast, and is essentially wedged into the backyards of several residential neighborhoods, where childhood asthma problems are common. Worries about a potential cataclysm run deep.