The VI-Suite Wind Rose node creates a wind rose plane and a wind rose image based on the location data within the location node. The location node must be drawing its information from an EPW file to provide wind speed data. EPW files must be placed within the VI-Suite script directory in the directory EPFiles/Weather to be seen by the node. A typical node arrangement is shown below.

The wind rose node requires some dependencies to be installed which I dealt with in a previous blog post for OS X. Please note that as of Blender version 2.70 Numpy is installed with the OS X version of Blender and the installation of Numpy described in my previous blog post will not be required.
Installing these dependencies for Windows is more complicated and I have not figured out an easy way to achieve this yet.
On Linux, Numpy and matplotlib should be installed via your system’s package manager system and the /usr/share/blender/’blender_version‘/python directory deleted to force Blender to see the system Python installation.
The operation of the Wind Rose node is shown in the short video below.

VI-Suite Wind Rose Node from Ryan Southall on Vimeo.