upcoming vs coming

upcoming is not a noun while coming is a noun.

Word	Noun	Adjective	Verb	Adverb
upcoming	No	Yes	No	No
coming	Yes	Yes	No	No

As adjectives, upcoming and coming are synonyms defined as:

Other synonyms of upcoming include approaching, forthcoming.

upcoming (noun)	coming (noun)
	the moment of most intense pleasure in sexual intercourse
	arrival that has been awaited (especially of something momentous)
	the act of drawing spatially closer to something
	the temporal property of becoming nearer in time

upcoming (adjective)	coming (adjective)
of the relatively near future	of the relatively near future