Aviation Weather Resources

Aviation Weather: The flight Safety Foundation

Aviation weather is more than just a general forecast; it involves specific meteorological elements and hazards that directly influence an aircraft’s performance and the flight environment.

Key Weather Elements

Pilots must consider how the atmosphere impacts their aircraft from the ground up:

  • Wind: Winds are reported by speed and direction, often relative to true north (as opposed to magnetic).

    • Headwinds slow the aircraft’s ground speed, increasing flight time and fuel burn.

    • Tailwinds increase ground speed, shortening flight time.

    • Crosswinds blow perpendicular to the runway and can make takeoff and landing challenging.

    • Wind Shear is a sudden, drastic change in wind speed or direction over a short distance, which is particularly hazardous during takeoff and landing.

  • Temperature and Pressure: These determine air density. Warmer, less dense air and lower pressure reduce an aircraft’s lift, engine performance, and climb rate. An accurate altimeter setting (barometric pressure) is essential for correct altitude readings.

  • Visibility and Ceiling:

    • Visibility is the greatest horizontal distance at which objects can be seen and identified

    • Ceiling is the height of the lowest layer of clouds or obscuring phenomena (like fog) that covers more than half of the sky (broken or overcast). Low visibility and ceilings can prevent a pilot from flying under Visual Flight Rules (VFR), requiring them to use instruments instead.

Significant Flight Hazards

Certain atmospheric conditions pose substantial risks to air travel:

  • Icing: Occurs when supercooled water droplets freeze upon contact with the aircraft’s surfaces. Ice accumulation is dangerous because it distorts the wing’s shape (reducing lift) and adds weight.

  • Turbulence: Caused by irregular air motion. It can be due to high winds, jet streams, convection (rising warm air), or mountain waves. It is categorized from light to severe and can affect passenger comfort and flight control.

  • Thunderstorms: These are one of the most dangerous weather phenomena for aviation. They contain severe turbulence, wind shear, hail, and lightning. Pilots are trained to avoid them by a safe margin.

  • Fog/Mist/Haze: These phenomena reduce visibility, which can lead to flight delays, diversions or accidents, especially during the critical phases of takeoff and landing.

Essential Aviation Weather Reports and Forecasts

Pilots use highly standardized, coded reports to get precise, up-to-the-minute weather information:

  • METARs: Aviation Routine Weather Reports. An observation of current weather conditions at an airport, issued hourly.

  • TAFs: Terminal Aerodrome Forecast. A forecast of expected weather conditions for a specific airport within a 24- or 30-hour period.

  • PIREP: Pilot Report. A non-standardized report of actual weather conditions encountered by an aircraft in flight, such as turbulence or icing.

  • SIGMET: Significant Meteorological Information. An advisory for non-convective weather conditions that are potentially hazardous to all aircraft, like severe icing, severe turbulence, dust storms, or volcanic ash.

  • AIRMET: Airmen’s Meteorological Information. An advisory for weather conditions that may be hazardous to smaller or less capable aircraft, issued for conditions like IFR (Instrument Flight Rules) or moderate turbulence.

Aviation Weather Resources

When preparing for a flight, pilots access official weather data from government agencies and specialized services.

Official Government Sources

These are the authoritative sources for aviation weather in the United States:

  • Aviation Weather Center (AWC): maintained by NOAA/NWS, this is the primary source for official aviation weather products like METARs, TAFs, SIGMETs and the Graphical Forecasts for Aviation (GFA).

  • Flight Service (1-800-WX-BRIEF): Provides official pre-flight weather briefings, flight planning, and flight plan filing services via phone or online portal.

Visual and Planning Tools

These resources are widely used by the aviation community for visual planning and data interpretation:

  • Graphical Forecasts for Aviation (GFA): An interactive tool on the AWC website that provides graphical displays of weather parameters, including turbulence, icing, winds aloft, and cloud ceilings/visibility.

  • SkyVector: An online flight planning tool that overlays aviation weather data (METARs/TAFs, winds) directly onto aeronautical charts.

  • Windy.com: A highly visual, interactive weather forecasting service popular for its detailed wind flow animations, though it should be cross-referenced with official products.

  • Fltplan.com (Garmin): A free, comprehensive flight planning and filing website used primarily by the general and corporate aviation community to created IFR/VFR routes, obtain performance calculations, and manage flight logistics.

  • Weather.com: A popular general consumer weather site that, while useful for basic trends and surface conditions is not an official source for legal FAA weather briefings required for flight planning.

  • ForeFlight: The industry-leading, subscription-based electronic flight bag (EFB) application used by pilots across general, business, and military aviation. It provides essential tools like interactive moving maps, digital charting, official FAA weather and flight plan filing, hazard warnings, and document management, consolidating everything a pilot needs for pre-flight an in-flight decision-making onto a single device.