Only one of the schools I am interviewing at has explicitly told me that the dress code is business formal, after they had let me know a few weeks before that it was going to be business casual, so I had to make a few changes. Anyway, all my interviews are at really cold places (compared to AZ), so I'll be wearing black tights because they're significantly warmer. This is with a black pencil skirt/blazer/heels combo but with a colored blouse. I also bought nude pantyhose just in case, I just rather not risk being uncomfortably cold.