This unbearably hot day "was broiling, almost the last, certainly the...
In chapter seven of The Great Gatsby by F. Scott Fitzgerald, the tense and tangled relationships in this novel all manage to collide, and they do so on an extremely hot summer day. That connection is no coincidence.
This unbearably hot day "was broiling, almost the last, certainly the warmest, of the summer." Daisy has invited Gatsby and Nick to come over for lunch, and Nick knows immediately that "[s]omething [is] up." On Nick's train ride over to the Buchanans, we hear and see ample evidence that it is hot and the heat is affecting everyone. People are tense and suspicious, and this foreshadows what is to come. At the house, everyone is rather sluggish; however, as soon as Daisy sends Tom out of the room, she goes to Gatsby, kisses him, and murmurs that she loves him. Trouble is brewing.
Of course we know that Tom has an epiphany at this luncheon. When Daisy tells Gatsby he looks "so cool" (an inverse connection to heat), Tom can hear the love in Daisy's voice (that voice which has the power to move people). Once Tom has this knowledge, the already-hot day becomes even more heated.
Tom gets more arrogant and pushy, Daisy gets more flirtatious, and Gatsby becomes more strained; Jordan and Nick just go along for the ride, literally. They all decide to go to town, and on their way Tom, Nick, and Jordan make a stop which gets even more events spinning into action on this stifling hot day. Nick says:
The relentless beating heat was beginning to confuse me and I had a bad moment there before I realized that so far his suspicions hadn't alighted on Tom. He had discovered that Myrtle had some sort of life apart from him in another world, and the shock had made him physically sick
Tom is struck hard by the news that the Wilsons will be moving; in the course of an hour or so, Tom suffers two losses and things are going to get worse, as is this unbearable heat.
In their hotel room things heat up even more, both literally and figuratively. Tom becomes the aggressor and Gatsby is unwilling to walk away; in fact, he wants to engage Tom and do battle for Daisy. When it comes right down to it, however, Daisy cannot be what Gatsby needs her to be. She is honest enough to say, "I did love him once--but I loved you too."
This marks the beginning of the end of this day. Tom is angrier, Gatsby is crestfallen, and Daisy just wants everything to be okay again somehow. Gatsby and Daisy drive off, and Daisy is so upset that she hits a woman with her car. Ironically, of course, she killed Tom's mistress, opening the way for him to give her his full attention, at least for now. Gatsby still dreams, but it is a hollow dream. Tom has won back Daisy, and they deserve each other.
The chapter is replete with references to the heat, and surely that is an apt setting for this chapter in which everything explodes and some things even die--Myrtle Wilson and Gatsby's dreams. These events would have all played out in some way, at some time; the overwhelming heat of this day certainly contributes to the drama and the tension of the actions by all the characters on this day.