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20051028: Surface analysis, merged ship and metar

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  • Subject: 20051028: Surface analysis, merged ship and metar
  • Date: 28 Oct 2005 13:26:37 -0600
On Thu, 2005-10-27 at 17:50, address@hidden wrote:
> >My interpretation from
> >your goal was that you wanted hourly sfmap plots,
> 
> no. my goal was to combine ship-buoy / metar data so that i can 
> improve my current hourly sfmaps to smooth color-filled more 
> professional looking hourly sufmaps.
> 
> what i have now is something like this
> http://weather.bgsu.edu/data/surface/temp.html
> 

Patrick,

OK...that makes a difference in my answer. If you
wanted to combine observations from multiple surface files into
a single surface file (for improved filtering/plotting with SFMAP),
an example is found in a support reply I made several years ago:
http://www.unidata.ucar.edu/support/help/MailArchives/gempak/msg01860.html

You could then, as usual, grid the data using oabsfc to a file
created with gdcfil/

Instead, since you want to grid the data, you can skip that merging
step and just specify both surface file in the SFFILE input to oabsfc:

1) Create a new grid file (either using the cpyfil parameter in GDCFIL,
or specifying your area). For example:


 GDOUTF   = newgrid.gem
 PROJ     = str/90;-95;0
 GRDAREA  = 17;-119;48;-60
 KXKY     = 600;450
 MAXGRD   = 5000
 CPYFIL   =  
 ANLYSS   =  
 GEMPAK-GDCFIL>

2) Use OABSFC to grid the data. You can
also improve your analysis over data void/sparse region using a first
guess field. I'll show an example of this. If you don't need that, then
just leave GUESS and GUESFUN blank:

 SFFILE =
$GEMDATA/surface/20051028_sao.gem+$GEMDATA/ship/2005102812_sb.gem
 GDFILE   = newgrid.gem
 SFPARM   = tmpc;dwpc;uwnd;vwnd;pmsl
 DATTIM   = 1200
 DTAAREA  =  
 GUESS    = gfs|051028/1200
 GUESFUN = tmpc@2%hght;dwpc@2%hght;urel@10%hght;vrel@10%hght;pmsl@0%none
 GAMMA    = 0.3
 SEARCH   = 20
 NPASS    = 2
 QCNTL    =  
 OABND    =  
 GDATTIM  =  
 GFUNC    =  
 GLEVEL   = 0
 GVCORD   = none
 GEMPAK-OABSFC>r

 OABSFC PARAMETERS: 

 Output grid file:        newgrid.gem
 Number of x, y points:   600   450
 Grid bnds:     17.00  -119.00    48.00   -60.00  Grid xtnd:    2   2  
2   2
 Station spacing:           0.17
 Guess grid file:  gfs|051028/1200
 Guess time:  051028/1200F000
 Surface file:           
$GEMDATA/surface/20051028_sao.gem+$GEMDATA/ship/2005102812_sb.gem
 Data area:               16.00;-140.00;56.00;-59.00
 Parameters:              TMPC  DWPC  UWND  VWND  PMSL
 QC threshold:             0.0   0.0   0.0   0.0   0.0
 Time:                   051028/1200         
 Grid date/time:         051028/1200         
 Grid functions:           TMPC  DWPC  UWND  VWND  PMSL
 Vertical levels:          0           0           0          
0           0         
 Vertical coordinates:     NONE        NONE        NONE       
NONE        NONE      
 GAMMA: 0.30   SEARCH:  20.00  NPASS:  2
 Valid blocking
bounds:                                                                         
                                                         
 No data extrapolation will occur. 
Enter <cr> to accept parameters or type EXIT:

 Processing data at time 051028/1200         

 RMS values for pass  0
   PARAMETER:     TMPC    DWPC    UWND    VWND    PMSL
   RMS:           3.15    2.68    1.63    2.02    1.13
   #STN:          2039    1895    2031    2031    1415

 RMS values for pass  1
   PARAMETER:     TMPC    DWPC    UWND    VWND    PMSL
   RMS:           1.34    1.23    0.70    0.84    0.64
   #STN:          2039    1895    2031    2031    1415

 RMS values for pass  2
   PARAMETER:     TMPC    DWPC    UWND    VWND    PMSL
   RMS:           1.12    1.04    0.59    0.68    0.60
   #STN:          2039    1895    2031    2031    1415



Steve Chiswell
Unidata User Support