Terminal Area Forecast (TAF), airport forecasts, are issued:
- for 30 airports throughout Sweden
- every six hours, valid for 24 hours for Stockholm - Arlanda, Stockholm - Skavsta, Göteborg - Landvetter and Malmö
- every third hour for other airports, valid for up to 9 hours, where the validity period is limited by the airport’s opening hours
The forecast is based on all available weather information, with an emphasis on METAR, airport observations, for each airport. The forecasts are followed up continuously by comparing with the latest METAR and, if necessary, the forecasts are changed, a so-called AMD TAF.
Observations, so-called METAR and METREPORT, at airports are carried out by local air traffic control.