Fashion Police!?

I know (or at least think) that it is okay to wear sleeveless tops and sleeveless tail dresses to go out and for special occasions even when it isn't warm out yet. So my question is what do you wear over it while you are outside - I'm afraid my coats and jackets would look ridiculous. I have a fab date this weekend at a ritzy place so I wanted to wear a little black dress. Thanks.