| Information
| Eample
|
| The first line
|
| 1.Locationindicator of the air traffic services unit serving the FIR (UIR) or control area to which the SIGMET message refers.
| YUDD
|
| 2.Message identification and consecutive day number
SIGMET is used for subsonic cruising levels.
SIGMET SST is used for transonic and supersonic cruising levels.
The SIGMET number corresponds to the
number of SIGMET issued for the FIR since
0001 UTC.
SIGMET and SIGMET SST messages use separate series of sequence numbers.
| SIGMET 2
|
| 3. Day-Time group.
Code for the following period (VALID)
Beginning of the validity period UTC (6 figures)
END of the validity period UTC (6 figures).
The validity period of SIGMET is preferable
not more than 4 - 6 hours.
| VALID 221215/
|
| 4.Issuing meteorological office followed by a hyphen to separate the preamble from the text message.
| UKBB-
|
Table 8. End
| Information
| Example
|
| The next line
|
| 5. The name of FIR (UIR) or control area for which the SIGMET is issued
| AMSWELL FIR
|
| 6. Phenomenon description or weather condition.
Each SIGMET includes only one dangerous weather phenomenon or weather condition (taken from the list above).
| EMBD TSGR
|
| 7. The information type: if phenomenon is observed and expected to continue abbreviation “OBS” is used. If phenomenon is forecast abbreviation “FCST” is used. Relevant time of observation is also given in UTC.
| OBS
|
| 8. Phenomenon or weather condition location.
The part of FIR or longitude and latitude degrees or well-known geografical features and flight level are indicated.
| TOP FL 300 S OF N50
|
| 9. Movement or expected movement of phenomenon.
It is given with reference to one of eight points of compass given in KMH or KT.
| MOV NW 40 KMH
|
| 10. The forecast change in phenomena intensity:
Intensifying, weakening or no change.
| INTSF, WKN or NC
|
| | | |
The list of abbreviations used when SIGMETs are composed is given in appendix 3 of this manual.
The one of the possiblevariant of SIGMET weather information indication at the terminal of air traffic controllers is given in Fig.2.
Fig.2. Indication of weather information at the terminal of air traffic controllers (SIGMET) (www.softaero.ru)
