EMMA warning
Introduction/Additional information:
The EMMA warning shall be used to warn shippers using graphical symbols on the ECDIS screen of heavy weather conditions. The following message is capable of transmitting the EMMA data using the AIS channel. It will not replace the Notices to Skippers warnings.
This message should be sent by base stations only, to give weather warnings to all vessels in a certain area. The message should be sent with binary message 8 on demand.
Registrant:
EU
DAC:
200
FI:
23
State:
in force
Number of slots (max):
2
Permitted as from:
10/10/2007
Details:
| Parameter | Bit | 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. Default = 0; 3 = do not repeat any more |
| Source ID | 30 | MMSI number |
| Spare | 2 | Not used, should be set to zero. Reserved for future use. |
| Application Identifier | 16 | As described in Table 2,6 |
| Start date | 17 | Start of validity period (YYYYMMDD), Bits 18-10: year since 2000 1-255 0 = default) Bits 9-6: month (1-12 0 = default) Bits 5-1: day (1-31 0 = default) |
| End date | 17 | End of validity period (YYYYMMDD), Bits 18-10: year since 2000 1-255 0 = default) Bits 9-6: month (1-12 0 = default) Bits 5-1: day (1-31 0 = default) |
| Start time | 11 | Start time of validity period (HHMM) UTC Bits 11-7: hour (0-23 24 = default) Bits 6-1: minute (0-59 60 = default) |
| End time | 11 | End time of validity period (HHMM) UTC Bits 11-7: hour (0-23 24 = default) Bits 6-1: minute (0-59 60 = default) |
| Start longitude | 28 | Begin of the fairway section |
| Start latitude | 27 | Begin of the fairway section |
| End longitude | 28 | End of the fairway section |
| End latitude | 27 | End of the fairway section |
| Type | 4 | type of weather warning: 0 = default/unknown, others see ANNEX B: EMMA CODES Table B.1 |
| Min value | 9 | Bit 0: 0 = positive, 1 = negative value = default Bits 1 – 8 = value (0 – 253 254 = 254 or greater, 255 = unknown = default) |
| Max value | 9 | Bit 0: 0 = positive, 1 = negative value = default Bits 1 – 8 = value (0 – 253 254 = 254 or greater, 255 = unknown = default) |
| Classification | 2 | classification of warning (0 = unknown/default, 1 = slight, 2 = medium, 3 = strong/heavy) according to ANNEX B: EMMA CODESTable B.2 |
| Wind direction | 4 | direction of wind: 0 = default/unknown, others see ANNEX B: EMMA CODESAnnex B Table B.3 |
| Spare | 6 | not used, should be set to zero. Reserved for future use. |
| 256 | occupies 2 slots |
Table 2.12: Weather type code
| Code | Description (EN) | AIS |
|---|---|---|
| WI | Wind | 1 |
| RA | Rain | 2 |
| SN | Snow and ice | 3 |
| TH | Thunderstorm | 4 |
| FO | Fog | 5 |
| LT | Low temperature | 6 |
| HT | High temperature | 7 |
| FL | Flood | 8 |
| FI | Fire in the forests | 9 |
Table 2.13: Weather category type code
| Code | Description (EN) | AIS |
|---|---|---|
| 1 | Slight | 1 |
| 2 | Medium | 2 |
| 3 | strong, heavy | 3 |
Table 2.14: Wind direction code
| Code | Description (EN) | AIS |
|---|---|---|
| N | North | 1 |
| NE | North east | 2 |
| E | East | 3 |
| SE | South east | 4 |
| S | South | 5 |
| SW | South west | 6 |
| W | West | 7 |
| NW | North west | 8 |