When we watch the local weather reports, the weather person appears to be pointing at incoming cold fronts or rain or heat, but in reality that person is standing in front of a blank usually green board. Here's Chester Lampkin of Channel 5 in St. Louis this morning.
Here's Jim Kantori of the Weather Channel.
Here's one explanation on how this is done. First they superimpose the weather person onto a computer monitor which has the weather map. These computers are to the side and in front of the forecaster. "To keep track of where he/she is pointing, they look at the monitors on each side of the blue or green screen." It takes practice for sure. Most newsrooms have a green screen which is why most weather people never wear green clothes even on St. Patrick's Day.
Here's a woman who did wear green and she disappeared except for her face.