Table B7
| Explanation of Data Designators T1T2A1A2ii CCCC |
| TABLE B7 Data type designator T2 (when T1 = L) |
| Instructions for the proper application of the level designators |
| (1) | The designator specified in this table should be used to the greatest extent possible to indicate the type of data contained within the text of the bulletin. |
| (2) | Where more than one type is contained in the text, the designator for one of the data types should be used. |
| (3) | When the table does not contain a suitable designator for the data type, an alphabetic designator which is not assigned in the table should be introduced and the WMO secretariat notified. |
| T1 | T2 - Data Type | GTS priority | Code form name |
| A | Aviation routine reports ("METAR") | 2 | |
| C | Aerodrome Forecast ("TAF") (VT < 12 hours) | 3 | |
| K | Tropical cyclone advisories | 3 | |
| N | Space weather advisories | 3 | |
| P | Special aviation weather reports (“SPECI”) | 2 | |
| S | Aviation general warning ("SIGMET") | 1 | |
| T | Aerodrome forecast ("TAF")) (VT ≥ 12 hours) | 3 | |
| U | Volcanic ash advisory | 3 | |
| V | Aviation volcanic ash warning ("SIGMET") | 1 | |
| Y | Aviation tropical cyclone warning ("SIGMET") | 1 |