Confused about times on soundings

Ok, so I was looking through soundings on and noticed they have 0000Z soundings for today. According to my calculations, that hasn't happened yet. What am I missing here? Am I just stupid and miscalculating, or are they going by a different time?


EDIT: I figured it out... I'm dumb. Its a new day going by GMT or Zulu, it just happens to start at 7:00PM CDT the previous day for us.