Shellie, it's kinda difficult to say... It could be 80 degrees and full sunshine. Or, it could be 50 degrees and drizzling. Or both - 80 one day, and 50 the next. I think the average temp for January is probably about 65 during the day. Because it's so humid, if it dips into the 40s or 50s at night, it feels pretty cold.
Best answer to your question - bring all of the above (shorts, jeans, sweatshirts and jackets).