How Do You Give A Weathercast?

How Do You Give A Weathercast?
SEATTLE - On TV, when you see the weathercast, it looks like we're standing in front of a wall that has our weather maps displayed on it.

But it's a television trick. What we're standing in front of is a blank, chartreuse-green wall. The camera has software that knows to replace the green color with the display from our weather computer. So on TV, it looks like we're standing in front of our weather maps instead of the blank green wall.

How do we know what we're pointing at? We have television monitors just off camera that show us in front of our map. When it looks like we're looking at the wall, we're actually looking at the TV monitor just off to the side. There's also a small monitor in the camera, so we can see the maps while looking at you at home.