The key element of the setting that you want to focus on is the snow at the ending of the story and the way that it freezes Ireland to a grinding halt. Note how it is described in the final paragraph as Gabriel Conroy looks at the snow through his window pane after his epiphany regarding his own life and how he has lived (or not lived) it:
Yes, the newspapers were right: snow was general all over Ireland. It was falling on every part of the dark central plain, on teh treeless hills, fallign softly upon the Bog of Allen and, father westward, softly falling into the dark mutinous Shannon waves.
What is important about this detail is the way in which the description conjures up an image of Ireland that is frozen or in a state of paralysis. Just as Gabriel realises that he has not really lived his life at all and that he has spent it worrying more about what others think about him than living a live "in the full glory of some passion" as Michael Furey did. He is a man that exhibits this sense of being frozen or suffering from paralysis in the way that he recognises that he has never truly loved and how he fears that he will "fade and wither dismally with age," in addition to the way that he dreams of using speech to reflect his passion but never actually does so, such as when he imagines making romantic overtures to his wife as they leave the party, or when he thinks of what he could say in response to Miss Ivors. The snow, that unites the living and the dead and freezes all of Ireland, thus is an important symbol reflecting the paralysis within Gabriel Conroy himself and the paralysis that Joyce felt characterised Ireland.