This is an Atom package for NCL (NCAR Command Language). It contains syntax and some useful snippets. It was based on a Sublime Text package by Li Dong.
To install, either:
Enter apm install language-ncl at your command line.
or
Search for language-ncl using the Atom package manager.
Then, open a new file in Atom with the suffix .ncl, and you are good to go!