
Dangerous, record-breaking heat will intensify across most of the central and eastern U.S this week. Heat indices will likely exceed 100 degrees. Severe thunderstorms are forecast from parts of the central High Plains into the Upper Midwest, and across parts of the Northeast. Critical fire weather conditions will continue across portions of the Four Corners and Great Basin. Read More >
Instructions for the proper application of the data type designator
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.
| Designator | Data Type |
| A | Radar data |
| B | Cloud |
| C | Clear Air turbulence |
| D | Thickness (relative topography) |
| E | Precipitation |
| F | Aerological diagrams (ash clouds) |
| G | Significant weather |
| H | Height |
| I | Sky/cloud cover |
| J | Wave height + combinations |
| K | Swell height + combinations |
| L | Plain language |
| M | For national use |
| N | Radiation |
| O | Vertical velocity |
| P | Pressure |
| Q | Web bulb potential temperature |
| R | Relative humidity |
| S | Snow cover |
| T | Temperature |
| U | Eastward wind component |
| V | Northward wind component |
| W | Wind |
| X | Lifted index |
| Y | Observational plot chart |
| Z | Not assigned |