The car windshield that was shot through during a road rage dispute in Park Slope today.

An NYPD 78th Precinct officer speaks to witnesses on the scene of the incident.

NYPD 78th Precinct officers speak to a witness on the scene of the incident.

The car windshield that was shot through during a road rage dispute in Park Slope today.

Apparently furious he’d been cut off, a road-raging gunman got out of his car and shot another driver in the head in Park Slope on Friday, shattering the afternoon calm of a quiet brownstone neighborhood, police sources said.

The shooter then got back in his car and drove off — and cops were still looking for him Friday night.

The victim, believed to be in his late 20s or early 30s, was rushed to Methodist Hospital in critical condition.

The shooter had been heading south on Sixth Avenue around 5 p.m. when he hopped out of his car and opened fire on the victim, who was stopped in his white sedan between First Street and Garfield Place, sources said.

The hot-head fired several shots in broad daylight before fleeing the scene in his car, which has New Jersey plates, police said.

Four bullet holes could be seen on the sedan’s front window as police investigated the scene Friday evening.

“As I drove around the cars that stopped, I saw [the shooter] holding a gun and pointing it at the driver’s windshield. I couldn’t believe it,” witness Onelfri Villar, 34, said. “I saw the first two shots and kept going to the red light as I heard the rest of the shots.”

Villar said he was “in shock” as he stepped out of his car and watched as bystanders leaped to the victim’s aid.

“I did get out but there were two other people already checking the driver’s condition,” he added.

Finnley Staub, 17, posted video to social media showing the aftermath of the shooting, as police and bystanders stand around the victim’s car.

Staub said he “heard exactly four gunshots” ring out before he headed to his window and hit record.

“So I was just chilling on my couch…and then all of a sudden I heard these loud sounds, which sounded a lot like firecrackers,” Staub told The Post.

And there I am scared half to death … and then I run to my window, and there’s this white car outside my building with people crowding around it.”

“I heard that earlier and I thought it was a car backfiring,” said a passerby who wouldn’t give his name. “I didn’t hear anything else afterward. So I’m just coming out now and it’s scary to find out it was actually a gun.”

Additional reporting by Olivia Bensimon