Beginner
This tutorial will be very short, focusing on the very basics of scripting with GrADS. It is the goal of this tutorial to provide a few pointers and tips to help the budding GrADS user avoid various (frustrating) pitfalls encountered while scripting with GrADS... Visit Tutorial Here
Basemaps are a great way to add some color and vibrance to your weather maps. This tutorial will show you how to make a basemap in GrADS, using topography data from the GrADS Data Sever... Visit Tutorial Here
Shapefiles provide you the possibility of plotting everything from county boundaries, to roads and rivers, to congressional districts, weather watches and warnings, and much more. This tutorial will give you a very basic introduction into using shapefiles in GrADS... Visit Tutorial Here
Vertical cross sections are very easy to plot in GrADS, requiring only that you fix either the latitude or longitude value, and vary the height levels. This tutorial will show you how to plot simple vertical cross sections using GrADS... Visit Tutorial Here
Hovmöller diagrams are very useful for determining the speed of various atmospheric disturbances, as it contours a variable in both time and space. It's very easy to plot a simple Hovmöller diagram in GrADS... Visit Tutorial Here
This tutorial is going to show you how to open more than 1 file at a time as well as address the main hiccups encountered when handling more than one file... Visit Tutorial Here
Intermediate
This tutorial teaches you how to save GrADS output onto an already existing image, a basemap. This allows you to bring more color and vibrance to your weather map by adding, for example, topographic maps underneath of your weather data... Visit Tutorial Here
GrADS is great for plotting model data, but did you know that you can plot RADAR and satellite data as well? This tutorial is very similar to the plotting satellite tutorial, and will take you through the steps of making plots with archived RADAR data from the National Climatic Data Center (NCDC)... Visit Tutorial Here
GrADS is great for plotting model data, but did you know that you can plot RADAR and satellite data as well? This tutorial is very similar to the plotting RADAR tutorial and will take you through the steps of making plots with archived satellite data from the CLASS data repository... Visit Tutorial Here
Plotting more than one shaded variable on the same map can prove frustrating as the new shaded variable continually plots over the old variable, even where the new variable is below the minimum value. However, there are a couple of ways to plot more than one variable on the same map without this issue... Visit Tutorial Here
Arrays can be an extremely useful tool when using loops in GrADS. Arrays reduce the number of lines in your code by a potentially large amount. For example, if you wanted to plot soundings at a number of different locations... Visit Tutorial Here
Making a correlation map in GrADS is actually quite simple. A regression/correlation map, is basically a map of regression and correlation coefficients plotted against a time-series of some variable. The classic example is the monthly average time-series of El-Nino vs. surface temperature on the globe... Visit Tutorial Here
This is the 2nd tutorial on using shapefiles in GrADS. If this is your first time using shapefiles in GrADS, it is recommended you check out this tutorial. This tutorial will dig a little deeper and look at the 'q dbf' command... Visit Tutorial Here
If you have ever attended a talk or a presentation, or read a paper for that matter, focused on modeling, you have likely encountered an image showing you the model domain with nested grid boundaries marked inside of it (see below)... Visit Tutorial Here
In addition to plotting gridded data, GrADS can also be used to plot station data. This tutorial will show you how to use some of the functions in GrADS to work with surface data from both the mesonet and METAR inventories to generate surface maps with and without contoured data... Visit Tutorial Here
There may come a time in your professional or student career when you will have to show a model grid overlaid on a map, to illustrate some sense of your model grid size. This approximation can be done fairly easily in GrADS using a little bit of spherical geometry, a couple of while loops, and the 'q w2xy' command... Visit Tutorial Here
Sometimes when plotting data on simple line graph it is useful to use colors to fill between different curves. For example, when plotting anomalies it may be helpful to fill the below zero values blue, and the above zero values red (see below figure)... Visit Tutorial Here
This tutorial will draw upon many of the skills discussed in several other tutorials on this site, e.g., how to handle multiple files at once, or how to use basemap.gs. This tutorial will show you how to specifically make a very pretty map of sea-surface temperature, sea ice, and snow... Visit Tutorial Here
Advanced
Since GrADS cannot easily perform high level data analysis techniques, (barring a few complicated workarounds) it may be useful to save data so it can be used with more advanced software. This tutorial will teach you how to save data using GrADS by guiding you through an example that will save latitude/longitude and monthly average surface temperature data... Visit Tutorial Here
This tutorial will teach you how to use the mfhilo function from the library of functions from Mike Fiorino made available in the newer versions of GrADS (v1.1 and newer) to plot H's and L's on a SLP map... Visit Tutorial Here
One of the major deficiencies with GrADS, is that drawing arbitrary vertical cross-sections is not an easy task. There are however work-arounds to do this, but they can be quite complex, especially when including terrain. This tutorial will guide you step by step through the process of plotting an arbitrary cross section in GrADS with terrain in pressure coordinates... Visit Tutorial Here
Here we go with yet another tutorial on using shapefiles in GrADS. This one is slightly more advanced than the other tutorials I have on this site: here and here. The reason it is a little more advanced is that, in this tutorial we will now use GrADS to create shapefiles as well as read them... Visit Tutorial Here
This tutorial will show you how to plot a possible storm track extending out from a storm center on RADAR. This tutorial will show you how to do this using two different methods... Visit Tutorial Here
some point, you may find it useful to be able to grab a subset of data from a larger data set, or from multiple data sets, and put it all in a custom GrADS data file with a matching control file. Luckily GrADS makes this possible through the use of the 'fwrite' function... Visit Tutorial Here
This tutorial will show you how to use a few of the widgets that come with GrADS to create basic Graphical User Interfaces (GUIs). We will use these tools, to create a functional calculator... Visit Tutorial Here
In this tutorial, I will be showing you how to write NETCDF files using Python, or some other language, which can then be read using GrADS using both the self describing 'sdfopen' and non-self describing 'xdfopen' commands... Visit Tutorial Here
Miscellaneous
If you are using GrADS through a linux operating system, chances are you are familiar with running GrADS from the command line, so this post is mostly aimed at the Windows users. This post will go through the basic instructions for running GrADS from your command line... Visit Tutorial Here
The finite differencing functions in GrADS are pretty handy, especially when it comes to plotting variables such as divergence... Visit Tutorial Here
There are a number of different possible map projections you can use in GrADS, and you may be familiar with some, or all of them, or perhaps you are only familiar with the standard default lat/lon projection used. This entry will be less of a tutorial and more of just a detailed look at the different map projections you can use in GrADS...Visit Tutorial Here
When using GrADS you will most likely run into a situation where you will have to use superscripts or subscripts, and Greek letters. This tutorial will provide some basic information on how to control the font in GrADS, including superscript/subscript syntax...Visit Tutorial Here
In using GrADS, you likely want to access metadata from the file, for example: The calendar date of your current time step, or your current latitude range. This post will serve as a reference table that includes code segments for many common metadata queries...Visit Tutorial Here
I've recently been involved with several discussions about how to communicate scientific ideas with good figures. I recently came across an open access BAMS paper discussing a shift from the traditional RGB color scales to an updated Hue-Chroma-Luminence (HCL) color scale. Here is a short blog post on how to use the HCL technique with GrADS...Visit Tutorial Here
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