Most certainly this is non-free. Download is only possible after registration, so I couldn't look into the distfile. We could add http://www2.ucar.edu/terms-of-use as the package's license, unless there's something better.
Masked for removal: http://sources.gentoo.org/cgi-bin/viewvc.cgi/gentoo-x86/profiles/package.mask?r1=1.15631&r2=1.15632
dropped