What is "Z" Time?
Since weather observations and forecasts are provided around the globe, it is important to understand when each piece of data is valid for. To overcome the problem of numerous time zones, it was internationally agreed upon that weather time stamps would be based on the Prime Meridian, or Greenwich Mean Time (GMT).
Other names for GMT include Universal Time Coordinated (UTC) or "Z" Time.
In the Mountain Time Zone:
Z = MST + 7 hours
Z = MDT + 6 hours
or
MST = Z - 7 hours
MDT = Z - 6 hours
examples: 11 am MST = 1800Z (6:00 pm GMT)
or
1800 MDT (6:00 pm) = 0000Z (Midnight the next day GMT)
Z = MST + 7 hours
Z = MDT + 6 hours
or
MST = Z - 7 hours
MDT = Z - 6 hours
examples: 11 am MST = 1800Z (6:00 pm GMT)
or
1800 MDT (6:00 pm) = 0000Z (Midnight the next day GMT)