The equation of an elliptical path can be defined as:

Where h = a randomly generated height between 10 and 60.
And t = time in seconds elapsed.
How can I start at a specific point when t = 0, and follow along the path as t increases, looping indefinitely?
It's actually easier than that. Position on an elliptical path over time is:
With
wandhthe width and height, respectively. Scaletas needed to get the speed you want.