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HOME > Monitoring_and_Data > Oceanic and Atmospheric Data > Reanalysis: Atmospheric Data > wgrib2 -set_ftime (new version v2.0.7)

wgrib2: -set_ftime


The wgrib2 inventory has a fragment that looks like

   :d=2014122500:12 hour fcst:vt=2014122512

   d=2014122500 is the Reference time, usually the analysis or start of the forecast time.
   12 hour fcst is the "ftime", the time is 12 hours after the reference time
   vt=2014122512 is the verification time (ref time + 12 hours)
Wgrib2 has options to change the reference time (-set_time) and to set the ftime. The -set_ftime v2 (introduced with wgrib2 v2.0.7) is easier to use and handles more Product Definition Templates. For compatibility, -set_ftime v1 is still available on wgrib2 v2.0.7+.

To change the ftime, you add the option -set_ftime FTIME. What are the allowed formats of FTIME? The formats are the same as ftimes from a wgrib2 inventory.

Original: :d=2014113018:6 hour fcst:
options:  -set_date 2014122500 -set_ftime "12 hour fcst"
New:      :d=2014122500:12 hour fcst:

Original: :d=2014113018:6 hour fcst:
options:  -set_date 2014122500 -set_ave "0-6 hour ave fcst"
New:      :d=2014122500:0-6 hour ave fcst:

Original: :d=2014113018:6 hour fcst:
options:  -set_date 2014122500 -set_ave "124@6 hour ave(0-6 hour ave fcst),missing=0"
New:      :d=2014122500:124@6 hour ave(0-6 hour ave fcst),missing=0:

After changing the time stamp, you can save the file with -grib NEW.grb

With wgrib2 v2.0.6 or earlier, you have to use -set_ave and -set_ftime. to convert betweent PDTs. Only a subset of the conversions are supported.

It was noted that the old ftime had problems with the more complicated time stamps and ftime2 was developed to be an eventual replacement. Similarily set_ftime2 was developed to replace the old set_ftime/set_ave options.

See also:

NOAA/ National Weather Service
National Centers for Environmental Prediction
Climate Prediction Center
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College Park, Maryland 20740
Climate Prediction Center Web Team
Page last modified: May 15, 2005, April 2020
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