There are several words in Chinese that express various degrees of probability/possibility/likelihood, such as 也许，说不定，可能，确定，etc.
Many of these words have overlapping definitions, but this may or may not mean that the different words convey a similar sense of probability.
What are the various "probability" words/phrases used in Chinese and how do their senses of probability compare with each other?
For example, in English and according to this native English speaker's sense (which will not be the same for all native English speakers), we have:
impossible < very unlikely < unlikely < potentially ~< maybe ~= possibly ~= perhaps < quite possible < likely < very likely < almost certain < definitely = certain
where I have ranked the words in order of their sense of likelihood (from least to greatest). I know I am missing words/phrases, but I hope this gets the idea across. I also know that I am mixing adverbs and adjectives; this is intentional as I am thinking about the core meanings and because the meaning can change between adjectival and adverbial forms (possibly vs possible, for example).
There is a related question, but I am looking for more words and a general sense of relative likelihood.