At a certain point, you think you have a good grasp of what to expect from weather graphics. A color-coded map, a five-day forecast with a sassy cloud. Which might be why the Weather Channel’s 3-D, room-encompassing depiction of the Hurricane Florence storm surge took so many by surprise. It doesn’t tell, it shows, more bracingly than you’d think would be possible on a meteorological update. Here’s how they did it.

If you haven’t seen the graphic yet, take a moment to watch the segment below. It starts normally enough, with a top-side view of the Eastern seaboard, showing the “reasonable worst-case scenario” of water levels. (The data comes from the National Hurricane Center.) But about 45 seconds in, a shift occurs. Meteorologist Erika Navarro stands not in a studio, but on a neighborhood street corner. And then the waters around her start to rise.

On one level, yes, the visualization literally just shows what 3, 6, and 9 feet of water looks like. But it’s showing that in a context most people have never experienced. It fills in the gaps of your imagination, and hopefully underscores for anyone in a flood zone all the reasons they should not be.

A year ago, this wouldn’t have been possible. In fact, this specific demonstration wouldn’t have been possible a month ago. The Weather Channel only finished the new “green-screen immersive studio” at its Atlanta headquarters this week. With peak hurricane season coming, it wanted to be prepared. “It was all hands on deck,” says Michael Potts, TWC’s vice president of design.

Fortunately, they’ve already had some practice with this sort of thing. About 18 months ago, Potts says, the broadcast industry at large started getting serious about the quality of graphics it could offer, thanks in part to the rising popularity of esports. Seeing potential for weather coverage, TWC invested in the use of Unreal Engine, the same suite of tools that powers countless video games. (Yes, including Fortnite.)

Working with the Future Group, a company that specializes in “interactive mixed reality,” TWC began building out the various elements it would need to make extreme—or mundane, if there were ever cause for it—weather events feel like they were happening in-studio. In June, it buzzed anchor Jim Cantore with a tornado. In late July, it blasted lightning.

But as impressive as those previous demonstrations were, they lacked the immersiveness and fidelity that Thursday’s Hurricane Florence display provided. That’s because of both the wraparound green screen, which helps completely surround Navarro, and the immediacy of the data the graphic is based on.