Getting Rid of Annoying "Red Warning Text"

[:1]Is there a way to get rid of the red warning text on the top of your screen?

Highlighted here in a green circle:
|||I might be wrong on this, but I think that's the default Blizzard UI, telling you that you're in the middle of a cast (for example).

I'm not sure that there's a way to suppress the text. You might try using macros that cancel any casting before starting the one you want, but that might not be the behaviour that you need.