What To Pack For A 2 Week Stay In Atlanta, GA (Summertime)!? [Female!]?

I am leaving for ATL in 7 days and am staying from the 28th to the 10th of July. Along with going to the beach i am also attending a Tom Petty concert =) So any suggestions on a packing list? Oh and when should I start packing. I mean I don't want to pack to early or to late! Thanks!