Hi,
There is only a possibility to display one colour overlay at a time. It is possible to combine wind barbs, temperature values and a number of iso lines at the same time together with one colour map.
I checked the display of "Windy" which has perhaps the best graphic weather display possible and they only display one colour overlay at a time. I.e. it is not possible to show clouds and rain at the same time on Windy.
David