“We’re not gonna let winter stop us,” says Mike Killion, a 31-year-old Chicago photographer who belongs to a small but growing tribe of surfers braving Lake Michigan’s waters long after the rest of us have deserted the beaches. Cold weather tends to bring bigger waves, in part because of the way the denser air and water interact. Some of the best local winter surfing, says Killion, is found near the steel mills and refineries of Whiting, Indiana, just outside Chicago.

The sport is not for novices. Sudden buildups of shoreline shelf ice can make getting back onto the beach difficult, even dangerous, and boulder-size bergs on the open water can be a hazard too. This is to say nothing of the frigid temperatures: Even with new-generation wetsuits, you can start to lose sensation and control in your hands and feet after a couple of hours. Just how cold does it get? “I’ve surfed on minus-20 days,” says Killion, “but when it’s that cold out, 33-degree water feels pretty good.”

Killion’s photographs — the ones on these pages were all shot in and around Whiting on January days — capture what feels like a hidden universe. “It’s so gnarly when you’re out there, so quiet, misty, and apocalyptic. You look around and realize, No one else in the world is experiencing this.”