rqt_plot set thresholds and alert

edit

I'm plotting a topic that is publishing integer messages (sensor readings). I would like to find a way to make it known when a message exceeds a set threshold. Ideally I would wish for it to be obvious on the graph itself.. this could be coloring the plot in a different color or creating threshold lines on the graph that makes it so that I can tell when the plot exceeds the set limit. It could also just be an alert on the GUI itself but not on the command line ideally.

Is there already such a plugin/a good way to do this or must I create a new plugin?

Cheers, Selin