National Weather Service United States Department of Commerce

Tracking Late Season Winter Storms

A moderate atmospheric river will continue to bring heavy snow over the Olympics, northern Cascades and northern Rockies Friday while heavy rain may bring flooding to coastal Oregon and Washington. A winter storm will continue to push across the Great Lakes and Northeast U.S. Friday and Saturday with areas of heavy snow and high winds. 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