What's the difference between "arguable" and "debatable"?

I have noticed that people use 'debatable' a lot, while 'arguable' is used quite less.
What's the difference and when should one use one or the other?

According to Merriam-Webster, both these words can be used to refer to something the truth of which is in doubt:

Debatable:

2a : open to dispute : questionable

Arguable:

1 : open to argument, dispute, or question

However, a second meaning for arguable is

that can be plausibly or convincingly argued

That is, arguable can be used to describe a proposition which someone wishes to present as true. Debatable, on the other hand (especially in light of the apparent synonymy of questionable), is often used to describe a proposition which someone wishes to present as false or at least unlikely; see for example Merriam-Webster's sample phrase

the debatable wisdom of going back for another helping from the buffet

which, it seems, would indicate that going back is presented as unwise.

Debatable means it could go either way. Arguable means that one can make a good case to support the issue/opinion.