What's the weather like in miami in january?

I really want to go to miami for my break during my fall/spring term. i want to know whats the weather like, and the beach too. I'm from New york and i've only been to florida once and it was for a day and i didn't get to go anywhere except for the hotel and the airport (woo hoo). So yes i would like to know what it's like from someone who's lived in miami during the winter months. Oh yeah i almost forgot and where to stay also. Thanks