We did a real last minute trip in 2013. After a week of blizzards, DW and I booked flights and CBR on Friday and flew out on Saturday. The lady at CBP was a little suspicious about such a last minute flight booking but once we described the weather at home, she simply said "I sure can't blame you for that." It was one of our best trips ever. We bought these silly lime green "Goofy Spring Break" t-shirts and we still refer to that one as our "Goofy trip".
Have a fantastic time!