A vital instrument in aviation, the Terminal Aerodrome Forecast (TAF) gives pilots, air traffic controllers, and meteorologists vital meteorological information. TAFs provide a comprehensive prediction for individual airports, encompassing anticipated weather trends within around five miles of the airport. This forecast is crucial for improving flight planning, guaranteeing safety, and foreseeing any possible weather-related delays. Here, we examine the definition of a TAF and the essential data it contains. METAR reports are also crucial in aviation for weather information, but they serve a different purpose. You can read more about METAR in our next article.
What Is a TAF?
A coded weather forecast designed especially for airport sites is called a Terminal Aerodrome Forecast, or TAF. A TAF concentrates on weather conditions that have a direct impact on airport takeoff, landing, and ground operations, as opposed to more general weather predictions. TAFs are available for major airports, including those with FAA-towered facilities, contract-towered, non-federal towered, and even some non-towered airports within the National Plan of Integrated Airport Systems (NPIAS). They are issued by meteorological authorities such as the Federal Aviation Administration (FAA) in the United States.
Although larger airports may give 30-hour forecasts to suit longer operational needs, TAFs typically provide a 24-hour forecast. These forecasts are updated four times a day in order to give pilots and dispatchers the latest information about conditions that are changing.
Key Components of a TAF
To interpret a TAF properly, you should know what it looks and sounds like and the specific components it includes. Here is an example made by the Australian Government of a TAF report. The following is a list of the key elements:
- Issue Time and Validity Period: The issue time, indicating the hour and minute the forecast was issued, is given first in the TAF. The next set of numbers/ letters indicates the validity period, usually 24 to 30 hours. If the forecast is designated, for instance, “2418/2518,” the forecast is valid from the 24th at 18:00 UTC to the 25th.
- Wind Another critical component of TAFs is wind. Wind is represented as speed, degrees, and direction of movement. Example: “26012KT” would indicate the wind is coming from 260 degrees at 12 knots. Also reported are gusts: “G20KT” indicates gusts up to 20 knots. There is also “00000KT,” which means the wind is calm.
- Visibility: This is the other important factor in considering landing and takeoff conditions. It is represented in terms of statute miles, such as “6SM”, representing six statute miles. Any reading less than 3SM would be considered reduced visibility. This could affect VFR operations and prompt a change to IFR.
- Weather Phenomena: Specific weather conditions are denoted by abbreviations; “RA” for rain, “SN” for snow and “TS” for thunderstorms while other symbols denote “BR” for mist, which help the pilots identify how bad the visibility is outside and the potential hazards that come with it.
- Cloud Cover Cloud cover information provides the number of cloud layers and their altitudes, which is critical when evaluating ceiling and planning approaches. The amount of coverage describes cloud layer(s) as “SCT” for scattered from 3/8 to 4/8, “BKN” for broken from 5/8 to 7/8, and “OVC” for overcast at 8/8.
- Additional Modifiers like “TEMPO” and “PROB” can be added to a TAF when transient changes in weather or probabilistic forecasts are issued. “TEMPO 2418/2422 2SM TSRA” means that on the 24th, from UTC 18:00 to 22:00, it is expected to have thunderstorms with low visibility for a short time.
Importance of TAFs for Pilots
TAFs give pilots vital information about weather patterns that aids in their decision-making. Pilots can choose different airports, modify flight plans, and be ready for IFR conditions if needed by predicting weather changes. Thus, TAFs are crucial to maintaining the dependability, effectiveness, and safety of aircraft operations.
Learn about NOTAMs in our previous article!