Hi Paul,
Thanks.
I ended up solving my original problem by correcting the longitude (needed a negative sign) and time zone (had been EST, changed to -5). I had not looked at the example in the help file carefully enough. Another suggestion would be to specify the format for the header fields (Lat, Lon, TZ, elev) explicitly in the help file (weather_format.htm) since SAM doesn't throw an error for an unexpected value.
Also, it appears that SAM puts the location data for the selected TMY file into the PDF report when specifying a weather file on disk. The attached PDFs show Ann Arbor, for example, when the weather file was from ORNL.
Regards,
Jeremy