UA.III.A.K3: Terminal aerodrome forecasts (TAF).

ACS Area III — Weather Task A: Sources of Weather References: ACAdvisory CircularCloseFAA guidance that explains acceptable ways to comply with rules or understand FAA procedures. 107-2; AIMAeronautical Information ManualCloseFAA operational guidance and glossary material used to understand aviation procedures and terminology.; FAAFederal Aviation AdministrationCloseThe U.S. aviation regulator responsible for Part 107 rules, airspace, and pilot certification processes.-H-8083-25; FAAFederal Aviation AdministrationCloseThe U.S. aviation regulator responsible for Part 107 rules, airspace, and pilot certification processes.-G-8082-22

Key Concepts

What a TAF Is and Why It Matters

• A Terminal Aerodrome Forecast (TAFTerminal Aerodrome ForecastCloseAirport forecast format used to reason about future weather conditions.) is an airport-specific forecast of expected weather conditions. It is produced within the national aviation weather system that includes NOAANational Oceanic and Atmospheric AdministrationCloseThe federal agency that includes the National Weather Service and aviation weather centers.’s National Weather Service (NWSNational Weather ServiceCloseNOAA agency that produces official U.S. weather observations, forecasts, and warnings.), the FAAFederal Aviation AdministrationCloseThe U.S. aviation regulator responsible for Part 107 rules, airspace, and pilot certification processes., the Department of Defense, and others, with the FAAFederal Aviation AdministrationCloseThe U.S. aviation regulator responsible for Part 107 rules, airspace, and pilot certification processes. serving as the U.S. Meteorological Authority that sets requirements for aviation weather products.^[1]
• TAFsTerminal Aerodrome ForecastCloseAirport forecast format used to reason about future weather conditions. are prepared by 123 NWSNational Weather ServiceCloseNOAA agency that produces official U.S. weather observations, forecasts, and warnings. Weather Forecast Offices (WFOsWeather Forecast OfficeCloseNWS office that prepares forecasts for its area, including many TAFs.) for over 700 airports. They are valid for 24 or 30 hours and are amended as required when conditions change.^[1]
• On the test and in practice, distinguish forecasts from observations: METARsMeteorological Aerodrome ReportCloseA current airport weather report format tested on the UAG exam. (observations) describe what is happening now; TAFsTerminal Aerodrome ForecastCloseAirport forecast format used to reason about future weather conditions. (forecasts) predict what will happen. Forecasts are based on observations and mathematical models and are intended to guide preflight and operational decisions.^[2][3]

Practical implications for a drone pilot: Use TAFsTerminal Aerodrome ForecastCloseAirport forecast format used to reason about future weather conditions. to anticipate time-based changes in wind, visibility, cloud cover, and weather that may affect small UASSmall Unmanned Aircraft SystemCloseA small drone plus the control and communication links used to operate it. operations during your intended flight window. While a METARMeteorological Aerodrome ReportCloseA current airport weather report format tested on the UAG exam. can be “green” at launch, a TAFTerminal Aerodrome ForecastCloseAirport forecast format used to reason about future weather conditions. might show deteriorating conditions later—essential for staying ahead of weather.

Validity, Updates, and Role in Preflight

• Validity period: Each TAFTerminal Aerodrome ForecastCloseAirport forecast format used to reason about future weather conditions. includes a defined forecast window, either 24 or 30 hours for the covered aerodrome.^[1]
• Amendments: TAFsTerminal Aerodrome ForecastCloseAirport forecast format used to reason about future weather conditions. are amended as required to reflect significant changes, so a later check can reveal updates that change go/no-go decisions.^[1]
• Preflight use: Federal regulations require pilots-in-command under 14 CFRCode of Federal RegulationsCloseThe federal rulebook where Part 107, Part 89, Part 48, and other aviation rules live. § 91.103 to become familiar with “weather reports and forecasts” before beginning a flight. While this regulation applies to Part 91, it underscores best practice for all aviation operations: integrate TAFsTerminal Aerodrome ForecastCloseAirport forecast format used to reason about future weather conditions. with other weather information during preflight.^[5]
• Forecasts are one of the five major categories of aviation weather information (with observations, analyses, advisories, and tools). Knowing this helps you structure your weather briefing: start with observations (e.g., METARMeteorological Aerodrome ReportCloseA current airport weather report format tested on the UAG exam.), review forecasts (TAFTerminal Aerodrome ForecastCloseAirport forecast format used to reason about future weather conditions.), scan advisories for hazards, and use tools that integrate multiple products.^[2]

Exam tip: Expect questions that ask you to identify what a TAFTerminal Aerodrome ForecastCloseAirport forecast format used to reason about future weather conditions. provides (a time-based forecast for a specific aerodrome), who produces it (NWSNational Weather ServiceCloseNOAA agency that produces official U.S. weather observations, forecasts, and warnings. WFOsWeather Forecast OfficeCloseNWS office that prepares forecasts for its area, including many TAFs.), how long it’s valid (24 or 30 hours), and that it can be amended.

Approved Sources and Supplementing a TAF

• Approved sources: The FAAFederal Aviation AdministrationCloseThe U.S. aviation regulator responsible for Part 107 rules, airspace, and pilot certification processes. permits use of aviation weather information from Federal Government sources (NWSNational Weather ServiceCloseNOAA agency that produces official U.S. weather observations, forecasts, and warnings./FAAFederal Aviation AdministrationCloseThe U.S. aviation regulator responsible for Part 107 rules, airspace, and pilot certification processes.), FAAFederal Aviation AdministrationCloseThe U.S. aviation regulator responsible for Part 107 rules, airspace, and pilot certification processes.-authorized Enhanced Weather Information Systems (EWINSEnhanced Weather Information SystemCloseAn FAA-approved system for producing or using aviation weather information in certain operations.), and Commercial Weather Information Providers. Commercial providers often repackage NWSNational Weather ServiceCloseNOAA agency that produces official U.S. weather observations, forecasts, and warnings./FAAFederal Aviation AdministrationCloseThe U.S. aviation regulator responsible for Part 107 rules, airspace, and pilot certification processes. products; if a commercial product substantially alters government-produced content, it may not be approved for operational decision-making.^[4]
• Internet caution: There is an expanding set of online and app-based products. The FAAFederal Aviation AdministrationCloseThe U.S. aviation regulator responsible for Part 107 rules, airspace, and pilot certification processes. does not certify internet providers of aviation weather services. Pilots should ensure they understand the content and proper use of any product they rely on for decisions.^[5]
• Supplementing a TAF: Use additional products to build situational awareness around the forecast. Examples that supplement NWSNational Weather ServiceCloseNOAA agency that produces official U.S. weather observations, forecasts, and warnings. or EWINSEnhanced Weather Information SystemCloseAn FAA-approved system for producing or using aviation weather information in certain operations. TAFsTerminal Aerodrome ForecastCloseAirport forecast format used to reason about future weather conditions. include:
  • AIRMETsAirmen's Meteorological InformationCloseA weather advisory for conditions such as turbulence, icing, mountain obscuration, or widespread low visibility. and SIGMETsSignificant Meteorological InformationCloseA weather advisory for significant hazards such as severe turbulence, severe icing, or thunderstorms. for widespread or significant hazards,
  • Center Weather Advisories (CWAsCenter Weather AdvisoryCloseA short-term aviation weather advisory issued by a Center Weather Service Unit.) for short-term hazardous conditions,
  • Graphical Forecasts for Aviation (GFAGraphical Forecasts for AviationCloseAviation weather forecast graphics used to review broad weather trends and hazards.) for a big-picture view,
  • Pilot Weather Reports (PIREPsPilot Weather ReportCloseA weather report from a pilot in flight, useful for confirming real conditions.) to validate forecast conditions,
  • Localized Aviation Model-Output Statistics (LAMPLocalized Aviation MOS ProgramCloseShort-range aviation forecast guidance that can supplement other weather products.) for short-range guidance,
  • FAAFederal Aviation AdministrationCloseThe U.S. aviation regulator responsible for Part 107 rules, airspace, and pilot certification processes. Aviation Weather Cameras (where available) for visual confirmation.^[7]
• Units and terms: Aviation weather commonly uses standardized units such as NMNautical MileCloseA distance unit used in aviation. One nautical mile is about 1.15 statute miles. (nautical mile) and SMStatute MileCloseA distance unit used for visibility in U.S. aviation weather reports. (statute mile) and acronyms like WFOWeather Forecast OfficeCloseNWS office that prepares forecasts for its area, including many TAFs. (Weather Forecast Office). Familiarity with these helps interpret TAFTerminal Aerodrome ForecastCloseAirport forecast format used to reason about future weather conditions.-related references and supporting products.^[8]

Key takeaway: For terminal-area planning, a TAFTerminal Aerodrome ForecastCloseAirport forecast format used to reason about future weather conditions. gives you the time-evolving forecast at an aerodrome; use it with real-time observations and hazard advisories from approved sources. Recheck close to flight time for amendments and corroborate with supplemental tools to ensure conditions remain within your operational limits.