| papers | Various papers and charts concerning this data set. |
| data_format | Format of the USAF station reports reformatted by NCDC |
| WMOtables.pdf | Various code tables. |
| horiz_vis_VV.pdf | Horizontal visibility at the surface code table. |
| precip_code_RR.pdf | Precipitation code table. |
| precip_group_note | Notes about the precipitation group '7RRjj' and max/min temperatures. |
| station_library_format | Format for the station library. |
| units | Notes about variable units. |
| codes.pdf | Chapter 12, Synoptic Code Description, Oct 1994. |