National Weather Service United States Department of Commerce

Heavy Rainfall and Severe Thunderstorm Threats; Heat Risk Expands; Monitoring the Tropics

Flash flooding risks continue for portions of the Four Corners and Great Basin through today. Severe thunderstorms are outlooked from the eastern Great Lakes, southern New England into the mid-Atlantic through Tuesday. Heat risk increases and expands across the center of the nation and across the Ohio Valley and mid-Atlantic this week. Continue to closely monitor tropical development in the Gulf. Read More >

 

Pictures from around western Colorado and eastern Utah
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)

Map of World Time Zones