A system and method for converting structured data to unstructured or structured data, the system and method receiving processing options in a flexible format and a reader selection, executing the reader selection to read data, computing a date time group to iterate through observed and/or modeled data, bilinearly interpolating the structured data to create an unstructured or structured finite element mesh, linearly interpolating data in time if necessary, and storing the populated grid on a computer-readable medium in a format compatible with a target numerical model.