What does the storm in chapter 18 symbolize?

In chapter 18, Janie sees a group of Seminole Indians walking past her house. They're off to seek higher ground in advance of an imminent hurricane. Janie has run off to the Everglades with Tea Cake in search of a more natural life. And their passionate, often tempestuous relationship is like a force of nature all of its own. But no amount of human passion is a match for the natural world and the destructive forces it unleashes.
Tea Cake acts all defiant in the face of the imminent storm, refusing to seek the safety of higher ground. But when the hurricane descends with all its terrible force, he soon regrets his foolishness. It's at that moment that Janie sees a rare vulnerable side to the normally strong, hyper-masculine Tea Cake. The hurricane allows Janie to put all of her problems into perspective. She can now see that the power exerted over her by Tea Cake and the likes of Mrs. Turner is nothing compared to the raw, unrestrained strength of the forces of nature. For all the control that Tea Cake and the racist society in which she lives exert over Janie's life, these pale into insignificance compared with what nature can do. In the overall scheme of things, the weak and the powerful alike are mere specks of life in the cosmos, their very existence controlled by a higher power, be it God or nature.