Why does the weather forecast of CCTV have to be told on the whiteboard?

Actually, it's not a whiteboard, it's a blue curtain, and the best effect is to add blue behind it.

First of all, it is inconvenient to speak directly to the chart, just like the weather forecast now. If you want to change several scenes, you can't change the picture for the time being.

The latter is more intuitive and can have an animation effect.

This is basically the case, because it is convenient and effective.