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OPC>FAQ>Graphical Product Legend>Terminology & Weather Symbols>Radiofacsimile User's Guide

 


Frequently Asked Questions
 
What is UTC, GMT, or Z time?

- By international agreement, the local time at the prime meridian or 0 degrees longitude, which passes through Greenwich, England.  Since there are 15 time zones across the world, UTC acts as a reference time for the scientific community. The terms Coordinated Universal Time (UTC), Zulu (Z), and Greenwich Mean Time (GMT) are equivalent. All of the analysis and forecast products are based on this reference time. This longitude is the line that separates the eastern and western hemispheres.

 
How do I determine when a chart was created? When is the forecast on the chart for?  

- "ISSUED" is the time and date for when this product was created by the forecaster

- "VALID" is the time and date for when the forecast depicted will represent the weather conditions

example

            

 

 

 


NOAA/ National Weather Service
National Centers for Environmental Prediction
Ocean Prediction Center
Attn: David Feit, W/NP41
5200 Auth Rd
Camp Springs, Maryland 20746

Phone: 301-763-8441
Fax: 301-763-8488 (SDM), 301-763-8085 (back office)


David.Feit@noaa.gov

Page last modified:  Friday, June 05, 2009
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