The colors in "The Storm" are seen in different situations, and represent different things, according to the scene. Some of the first mentionings of color are in describing Calixta's appearance. Her eyes are intensely blue, and her hair is yellow, shining and beautiful. This description comes in after Alcee has entered the scene, and symbolize how she must look to him at that moment. She looks stunningly beautiful, with luminous eyes and brilliant hair; it symbolizes her attractiveness to a man, and her ability to be powerful as a result. Kate Chopin took a strong interest in female empowerment, and these descriptions of Calixta's appearance serve to enhance her power over Alcee. Later, appearance is mentioned again the red of her lips as Alcee goes in for the kiss; they are "as red and moist as pomegranate seed." Comparing them to a red fruit symbolizes how appealing they are, sweet and desirable.
Color is also used to describe the bedroom. It is white, and glowing with a soft light. White is also used as to describe the bed that they lie on, Calixta's skin, and her "abundance of passion" is compared to a "white flame". All of these uses of white ironically symbolize the pure passion that they experienced together. It symbolizes what to Chopin is the purity of achieving one's happiness. White is usually a symbol of virtue, and Chopin uses it as a couple breaks their vows and are immoral; this makes a point that she feels that we should not feel guilty for doing something that brings so much happiness and fulfillment. Whether one agrees with that or not, the choice of the normally pure and virtuous white was a significant one for Chopin, to enhance her theme of female empowerment through personal choices that are sometimes unconventional.
I hope that those thoughts helped; good luck!