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New Aviation Weather Code for International Exchange

Due to the transmission speed of the telecommunication links decades ago, the aviation industry has been using a coded text form (so called the Traditional Alphanumeric Code, or TAC) for exchange of weather information including METAR, TAF, SIGMET and others. The existing format is very limited in expressiveness and prone to various kinds of errors during transmission and decoding. Moreover, due to growth in air traffic and the consequentially the demand for improved meteorological information for decision support to minimize disruption due to weather, a gap has been identified between the meteorological products being exchanged in TAC format and the evolving user needs.

Recently, the World Meteorological Organization (WMO) and the International Civil Aviation Organization (ICAO) joined hands to develop the next generation code for the exchange of aviation weather information. The new code, known as Aviation XML (AvXML), is developed by a team of experts in meteorology, air traffic management and information technology. The main target is to define a new representation of weather information which supports future mode of operations that requires more precise information that could be more readily handled by computers and eventually replace the TAC. The first version of the AvXML has been released in early May 2013 for public consultation and those who are interested can visit the following website for further details: