That's a winstreak bar. It means you've won at least two times in a row. It goes up by one every time you win, and goes down by a half if you lose. The ranks for winning is Chill, toasty, smoking, and the highest being SO HAWT!! (Yes, that's what it's called). Talking to Judd with one of these ranks will result in giving you a cash bonus. Each rank being more than the other. Now you know! Ugh...