Gribwind is basically a modified version of wgrib.c by W. Ebisuzaki

Use gribwind to extract and analyze wind data, specifically the UGRD
and VGRD wind components, and to output that data, as well as the
calculated wind speed and direction *directly* (no conversion necc.),
as text, or optionally as comma-delimited data.

Download the source code from http://weather.giwiganz.com

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Sample output:

GribWind -----------------------------------------------------
Wind Analysis for gulf.grb :24hrfcst: 2006.5.23.12
Latitude 30.0000 to 40.0000 by 1.0000 degrees (ny=11)
Longitude -96.0000 to -83.5000 by 1.2500 degrees (nx=9)
--------------------------------------------------------------
Coordinates Vector Components Winds (24hrfcst)
Lat. Long. U (m/sec) V (m/sec) speed(kts) dir (deg)
-------- --------- ---------- ---------- ---------- ----------
30.0000 -88.5000 -0.1400 -4.6900 9.1 2
30.0000 -87.2500 -0.5000 -1.9300 3.9 15
30.0000 -86.0000 -3.7000 1.3500 7.7 110
29.0000 -94.7500 1.6200 -0.8500 3.6 298
29.0000 -93.5000 3.9800 -0.4100 7.8 276
29.0000 -92.2500 2.3400 -2.9700 7.3 322
29.0000 -91.0000 4.5400 -4.2100 12.0 313
29.0000 -89.7500 3.0200 -0.6500 6.0 282
29.0000 -88.5000 -0.7800 -2.7300 5.5 16
29.0000 -87.2500 0.1800 -3.2900 6.4 357
29.0000 -86.0000 -2.3000 1.2700 5.1 119
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