Your gonna have to give us a summary of the selection because we don learn the same things you do. After you explain the summary maybe then we can help you with this question.
Im 99% sure that it is metaphor
Black friday is a time for catching deals and getting a head start on holiday shopping, but with some weird morality in its juxtaposition with Thanksgiving where black friday wrecked havoc after the Thankful holiday. Hope this helps :D
It's pouring down with rain when they meet up at Nick's house, and gradually the sky clears. It's a metaphor for the way things are going between them.