Metreorological and hydrological data
| Parameter | No. of bits | Description |
|---|---|---|
| Message ID | 6 | Identifier for Message 8 ; Always 8 |
| Repeat Indicator | 2 | Used by the repeater to indicate how many times a message has been repeated. |
| Source ID | 30 | MMSI number of source station |
| Spare | 2 | Not used. Should be set to zero. |
| IAI | 16 | DAC = 001 FI = 11 |
| Latitude | 24 | Measuring position, 0 to + /- 90 degrees, 1/1000th minute |
| Longitude | 25 | Measuring position, 0 to + /- 180 degrees, 1/1000th minute |
| Date and time | 16 | Time of transmission, Day, hour, minute, (ddhhmm in UTC) |
| Average wind speed | 7 | Average of wind speed values for the last 10 minutes. 0-120 kts, 1 kt |
| Wind gust | 7 | Wind gust is the maximum wind speed value reading during the last 10 minutes, 0 – 120 kts, 1 kt |
| Wind direction | 9 | 0 – 359 degrees ,1 degree |
| Wind gust direction | 9 | 0 . 359 degrees, 1 degree |
| Air temperature | 11 | Dry bulb temperature – 60,0 to + 60,0 degrees Celsius 0,1 of a degree |
| Relative humidity | 7 | 0 . 100%, 1% |
| Dew point | 10 | – 20,0 – + 50,0 degrees, 0,1 degree |
| Air pressure | 9 | 800 . 1200 hPa, 1 hPa |
| Air pressure tendency | 2 | 0 = steady, 1 = decreasing, 2 = increasing |
| Horizontal visibility | 8 | 0,0 . 25,0 NM, 0,1 NM |
| Water level (incl. tide) | 9 | Deviation from local chart datum, . .10,0 to + 30,0 m 0,1 m |
| Water level trend | 2 | 0 = steady, 1 = decreasing, 2 = increasing |
| Surface current speed (incl. tide) | 8 | 0,0 . 25,0 kts 0,1 kt |
| Surface current direction | 9 | 0 . 359 degrees, 1 degree |
| Current speed, #2 | 8 | Current measured at a chosen level below the sea surface, 0,0 . 25,0 kts, 0,1 kt |
| Current direction, #2 | 9 | 0 . 359 degrees, 1 degree |
| Current measuring level, #2 | 5 | Measuring level in m below sea surface , . 0 .30 m 1 m |
| Current speed, #3 | 8 | 0,0 . 25,0 knots, 0,1 knot |
| Current direction, #3 | 9 | 0 . 359 degrees, 1 degree |
| Current measuring level, #3 | 5 | Measuring level in m below sea surface, 0 . 30 m 1 m |
| Significant wave height | 8 | 0,0 . 25,0 m, 0,1 m |
| Wave period | 6 | Period in seconds, 0 . 60 s, 1 s |
| Wave direction | 9 | 0 . 359 degrees, 1 degree |
| Swell height | 8 | 0,0 . 25,0 m, 0,1 m |
| Swell period | 6 | Period in seconds, 0 . 60 s, 1 s |
| Swell direction | 9 | 0 . 359 degrees, 1 degree |
| Sea state | 4 | According to Beaufort scale (manual input?), 0 to 12, 1 |
| Water temperature | 10 | -10,0 – + 50,0 degrees, 0,1 degree |
| Precipitation (type) | 3 | According to WMO |
| Salinity | 9 | 0,0 . 50,0 ., 0,1. |
| Ice | 2 | Yes/No |
| Spare | 6 | |
| Total Number of bits | 352 | Occupies 2 slots |