| Abbreviation | Definition |
|---|---|
| C | Canada |
| C20 | Andrews University Airpark, Berrien Springs, Michigan USA |
| C62 | Kendallville Municipal Airport, Kendallville, Michigan USA |
| C71 | Crosby Municipal Airport, Crosby, Mississippi USA |
| C73 | Charles R. Walgreen Field, Dixon Municipal Airport, Dixon, Illinois USA |
| C77 | Poplar Grove Airport, Poplar Grove, Illinois USA |
| C83 | Byron Airport, Byron, California USA |
| C87 | East Cameron Block 299 Supplementary Aviation Weather Reporting Station, Gulf of Mexico |
| C91 | City of Dowagiac Municipal Airport, Dowagiac, Michigan USA |
| CAB | Cabinda, Angola |
| CAC | Cascavel, PR, Brazil |
| CAE | Columbia Metropolitan Airport, Columbia, South Carolina USA |
| CAG | Cagliari, Italy |
| CAI | Cairo, Egypt |
| CAJ | Canaima, Venezuela |
| CAK | Akron/ Canton, Ohio USA |
| CAL | Campbeltown, England, UK |
| CAN | Guangzhou, Mainland China |
| CAP | Cap Haitien, Haiti |
| CAQ | Caucasia, Colombia |