I struggle with the following problem: I have time series data I want to plot as a scatter plot – this is not problem with standard matplotlib.plplot.scatter.

However, Under the scatter plot I would like to plot vertival bars indicating events or time frames with special conditions related to the scatter plot data. Someting like this (never mind the rounded corners, they can be sharp):

How can I do this?
Note: Currently, I am working with matplotlib to produce the scatte plot. However, I am not fixed to this if my feature can be realized differently.