TAF

TAF means Terminal Aerodrome Forecast. It is a coded forecast for weather conditions expected within a defined terminal area, usually near an airport, during a stated validity period. A TAF commonly forecasts wind, visibility, weather, and cloud conditions. It is a forecast, not an observation.

How it works

A TAF begins with the station identifier and issue time, followed by its valid period. A line such as TAF KPHX 041730Z 0418/0524 means the forecast for Phoenix was issued on the fourth day at 1730Z and is valid from 1800Z on the fourth through 2400Z on the fifth.

The initial group describes the prevailing forecast. Later groups show expected changes. FM042000 means a new prevailing group begins at 2000Z on the fourth. TEMPO describes temporary fluctuations during a stated window. PROB30 indicates a 30 percent probability group where used by the applicable forecast format.

Example

In a simplified TAF, 24010KT P6SM SCT030 forecasts wind from 240° at 10 knots, visibility greater than 6 statute miles, and scattered clouds at 3,000 ft. A later FM042200 27015G25KT BKN020 group forecasts a change beginning at 2200Z, with wind from 270° at 15 knots gusting to 25 knotsand broken clouds at2,000 ft`.

Why it matters

The validity and change times determine which forecast group applies. A TAF can be updated or amended, and a forecast can differ from conditions later reported by a METAR. Check the issue time, valid period, and any amendments before using it for planning.

TAFs describe expected conditions at the terminal. They do not replace current observations, pilot reports, official briefings, or the applicable weather minimums and operating rules. The NOAA Aviation Weather Center API provides official aviation weather product information.

Related terms and tools

• METAR
• NOAA Aviation Weather Center API
• FAA Aeronautical Information Manual