The next day was broiling, almost the last, certainly the warmest, of the summer.
This is the hottest day of the summer that Daisy mentioned in chapter 1. Also, it’s towards the end of the summer which implies we are getting close to the end of this story. Strong heat usually brings out strong emotions, so it appears that we are finally going to see something big happen in the Daisy/Gatsby/Tom love triangle.
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