WeaTran: WeaTran reformats many common data types (such as TMY, TMY2, First Order Summary of the Day, etc.) into easy-to-read columnar or PRISM-ready data formats. In addition, it can calculate solar radiation on any surface (or on any four walls) using TMY or TMY2 data.

Download a free copy of WeaTran (About 1.5 MB, no user support or warranty provided)