How to plot GFS GRIB2 raw data with NCL (NCAR Command Language)

As mentioned in the previous blog post, I used the freely available GFS raw data from NCAR, stored in GRIB2 format, for plotting. NCAR also provides a own plotting language called NCL, which stands for NCAR Command Language. It’s a very useful tool to create both simple and very complex plots of meteorological data. It supports different data formats as e.g. GRIB2 and NetCDF to just mention the most common.
An alternative plotting tool that is commonly used to plot meteorogical data fields is GraDS.

In this post I want to share a simple plotting sample script for plotting a GFS T2m temperature field.
A wide variety of examples can be found at the official NCL page. But unfortunately there are no examples for GFS. So I hope this example can give you a good starting point.


New service: GFS plots

There are several sources for weather maps in the word wide web. Thanks to the open data policy of the United States the output of GFS (Global Forecast System) from NCAR is freely available for download in the internet. So everyone can use these data to produce own weather maps with the desired variables and in the desired style. Of course, one must have some knowledge of how to read the data and work it up to plots. During the last days i started to write some scripts that make it possible to auto-produce plots and upload these to this web project. At the moment there are only some plots available, but there is going to be a lot more soon. I’d appreciate any comments and suggestions on how to improve this service.
Notice that the GFS data is direct model output. I can not guarantee that the data is correct or that the scripts are free of errors.