Apr 26, 2015 - Download the most recent wgrib2.exe version and all DLL files from Wesley Ebisuzaki's web site: Click here. Step 2: Make a directory somewhere on your computer. I chose: C: Program Files wgrib2. Copy the.exe and the.dll files to this directory. Step 3: Append the directory path to the Windows PATH.

Two years ago, I wrote a software package for R called “rNOMADS” that interfaces with online weather and sea ice model repositories to gather data in real time, for free. The data are delivered in two ways: a simple, pure R, cross platform interface using GrADS-DODS, and binary files in GRIB format. The one issue with GRIB is that this format can’t be read directly into R; it requires the external program “wgrib2.” Installing rNOMADS with GRIB support for Linux is covered in (Mac OS is probably similar). I thought GRIB support for Windows was impossible until the guy who runs casually told me he’d figured it out. So, I finally got around to trying it myself, and I’m happy to say I got it to work! Here’s how: Step 1: Download the most recent wgrib2.exe version and all DLL files from Wesley Ebisuzaki’s web site: Step 2: Make a directory somewhere on your computer. I chose: C: Program Files wgrib2 Copy the.exe and the.dll files to this directory.

Step 3: Append the directory path to the Windows PATH variable. Find out how to do this. Edit: a user points out that sometimes this doesn’t work.

If not, change the path variable in R using Sys.setenv(): Sys.setenv('PATH' = 'C:/Program Files/wgrib2') Step 4: If R is open, close and reopen it. Then try the following command in the R interpreter: system('wgrib2') If you get a bunch of text that looks like the image below, you’ve succeeded. You can start reading GRIB files with rNOMADS!

Climate Prediction Center - wgrib2: -i -i_file Search CPC Search About Us Contact Us >>>>wgrib2-i -i_file wgrib2: -i, -i_file Introduction The -i option specifies that wgrib2 should read STDIN to determine the records to be processed. The -i_file option is similar except that wgrib2 reads file a user-specified file to determine the records to be processed. Some of the common uses of -i can also be done with the -match option. Slicing and Dicing Wgrib2 is a program to 'slice and dice' grib2 files. Suppose you have a big grib file but you only want the 2-meter temperature and the precipitation.

Rather than fill up your disk with big files, you can easily extract the required fields. The first step is to figure what is in the grib file. -sh-2.05b$ wgrib2 test.grb2 -s 1:0:d=:HGT:1000 mb:60 hour fcst 2:133907:d=:HGT:975 mb:60 hour fcst 3:263511:d=:HGT:950 mb:60 hour fcst 4:389058:d=:HGT:925 mb:60 hour fcst 5:511037:d=:HGT:900 mb:60 hour fcst 6:630256:d=:HGT:850 mb:60 hour fcst 7:745505:d=:HGT:800 mb:60 hour fcst. Error Installing License Demo License Previously Installed. 23:d=:GPA:1000 mb:60 hour fcst 22:d=:GPA:500 mb:60 hour fcst 21:d=:5WAVA:500 mb:60 hour fcst Information overload.

Lets see if you can find the desired variables. -sh-2.05b$ wgrib2 test.grb2 -s grep ':TMP:2 m' 28:d=:TMP:2 m above ground:60 hour fcst Found the 2-m temperature, can we find the precipitation? -sh-2.05b$ wgrib2 test.grb2 -s grep ':PRATE:' 29:d=:PRATE:surface:54-60 hour fcst Yes. We found the fields. Now we need to combine the above into a single command using the or option of egrep; i.e., egrep '(A B)'. -sh-2.05b$ wgrib2 test.grb2 -s egrep '(:TMP:2 m :PRATE:)' 29:d=:PRATE:surface:54-60 hour fcst 28:d=:TMP:2 m above ground:60 hour fcst Now that we have selected the records, we can send the output (inventory) back into wgrib2 to manipulate.