afi met bulletins exchange (ambex) handbook - ICAO

AMBEX HANDBOOK 7th Ed. 17/58
6. TAF EXCHANGE
6.1 General
6.1.1 Aerodrome forecast (TAF) should be prepared by the aerodrome meteorological offices
(AMOs) or other meteorological offices, designated for provision of TAF by the State’s meteorological
authority, for all international aerodromes, for which TAF is required according to FASID Table MET 1A
of the AFI ANP.
6.1.2 All TAFs required should be included in the regular AMBEX exchange. In addition, TAFs
from a number of other, including domestic aerodromes, required by the users, should also be included in
the regular AMBEX exchange, if so agreed by the States concerned.
Notes: 1) The recent requirement by airlines is that TAF for all international aerodromes
listed in AFI FASID Table MET 1A should be available through regular exchange
and through the satellite distribution system SADIS..
2) SADIS User Guide (SUG) Annex 1 presents the requirements for OPMET data
(METAR and TAF) by aviation users. When OPMET data from domestic airports
(so called non-AOP airports) is required by users, the corresponding State is
consulted on its agreement for providing this additional information. If the
information is available and the State agrees to include it in the exchange, the
additional airports are included in SUG Annex 1 and the State should provide the
additional OPMET information on a continuous basis.
6.1.3 TAF exchanges not covered by the AMBEX Scheme, but required operationally, should be
met by means of direct addressed AFTN messages.
6.1.4 The requirements for the exchange of 24 or 30-hour TAFs (so called “long” TAFs with
WMO data designator – FT), are set in FASID Table MET 1A of the ANP. “Short” TAFs with 9- or 12hour
period of validity (WMO data designator - FC), are no longer issued by States in the AFI region
6.1.5 AMBEX messages and bulletins are normally sent via the AFTN. In exceptional
circumstances, when the AFTN cannot give adequate support to AMBEX traffic, the temporary use of
alternative existing communications systems should as far as possible be coordinated with the ICAO
Regional Offices concerned.
6.1.6 Each AMBEX message and AMBEX bulletin should conform strictly to the Annex 10
message format.
6.1.7 Each AMBEX message and AMBEX bulletin should carry a WMO abbreviated heading
(see Appendix C).
6.1.8 Each AMBEX message or bulletin, should terminate with an equal (=) sign (signal no. 22
of International Telegraph Alphabet no.2 in the figure case).
6.1.9 The procedures described in this Handbook are intended for the manual preparation of
AMBEX messages and bulletins. It is not intended, however, that the Handbook precludes the use of
automated or semi-automated procedures. When required, the procedures described hereunder should be
modified and applied in a manner which will fully exploit the capabilities of the equipment available. The
AMBEX messages and bulletins produced by application of such modified procedures should be in a