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[GEMPAK #YSK-578220]: Filtering Surface Data

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  • Subject: [GEMPAK #YSK-578220]: Filtering Surface Data
  • Date: Thu, 12 Jan 2006 13:37:43 -0700
Charles,

There are several options for preventing the bad data from contaminating your 
plot.

1) If you know the station ID, such as in this case, you can eliminate it such 
as is 
shown in example #2 of the "phelp oabsfc". Eg, DTAAREA = data/-@dca;buf
will use all stations, expect DCA and BUF; Or, DTAAREA = data/-@CN:c would
use all stations, except those from the country Canada; etc...

In the case where you would want to routinely QC the data for an automated 
process,
you could restrict the data used in several ways:

2) Use a first guess field, and then specify the QCNTL value such that data 
outside of
QC threshold from the first guess could be deleted.

3) When creating your surface file, use the SFPRMF packing information to
specify the valid range of data for each variable- this is generally already 
done
if you create the file using one of the defined packing files, but
could be employed if you were creating a file using SFCFIL.

4) Restrict the gridding data range in OABSFC such as: SFPARM=tmpc<50
The GFUNC name allows you to control the parameter name, so you can use
the elementary functions that SFMAP provides.

Good luck,

Steve Chiswell
Unidata User Support


Ticket Details
===================
Ticket ID: YSK-578220
Department: Support GEMPAK
Priority: Normal
Status: Closed