When the adverb clause follows the main clause, there is usually no need for a comma. The air was raw, dank and gray. The comma immediately before the coordinating conjunction is optional. If items in a series contain internal commas, the semicolon is used instead of commas for clarity. Coordinating adjectives - adjectives that modify the same noun.
Sleep is a dark, quiet, peaceful luxury.
My mother, who had heard all of this before, smiled knowingly.