Some weather forecasters are just "presentable faces." But some are actual meteorologists who try to put effort into interpreting that data.

I used to work at a tv station and the Actual Meteorologists were very particular about not being confused with the "weather people."

Yes, you're right, I over-simplified. Many of them are (or have) meteorologists. To give the data itself a pretty face (interpretation). But that's not the primary reason that news stations hire "weather people". If it was, they would just contract out to some other company.