World Area Forecast Center
A World Area Forecast Center (WAFC) is a meteorological center that transmits meteorological information in real time for aviation purposes . These transmissions are under the supervision of the International Civil Aviation Organization (ICAO), and the necessary requirements of ICAO Annex 3 on the meteorological services that are necessary to carry out flights are covered. The task of the WAFCs is to provide meteorological reports with worldwide coverage for the briefing of pilots. These are usually part of the Pre-Flight Information Bulletin (PIB).
A WAFC provides different data: OPMET information, GRIB and BUFR diagrams - these relate to winds at high altitude and temperatures as well as SIGWX charts (Significant Weather Charts) for high and medium altitudes.
There are only two World Area Forecast Centers worldwide, each of which serves as a backup facility for the other. These are referred to as WAFC London and WAFC Washington, with London being responsible for Europe, Asia, the Indian Ocean and Africa and Washington for America and the Pacific region. These centers are operated by the British Met Office and the US National Oceanic and Atmospheric Administration . They work redundantly so that they can replace each other in the event of a failure. Each of these two services operates its own transmission system with which the airports around the world are served with data. The British system is called SADIS (SAtellite Distribution System). NOAA has now replaced its International Satellite Communications System (ISCS) with a system that runs over the Internet.