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    Weather station reports. True or magnetic

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    • ivoI
      ivo Administrator
      last edited by

      Even in METARs? I guess METARs use magnetic.

      Gkikas LGPZG R 3 Replies Last reply Reply Quote 0
      • Gkikas LGPZG
        Gkikas LGPZ Moderator Meteorologist @ivo
        last edited by

        @ivo
        I copy from https://www.faa.gov/air_traffic/publications/media/aim.pdf
        Chapter 7, section 1
        53f543bf-c994-49e8-a343-dc3784810a00-εικόνα.png

        1 Reply Last reply Reply Quote 3
        • G
          GiovanniV
          last edited by

          I am not familiar with weather reports in the flight sector but according to German weather service (DWD) it is reported in true north(German source: DWD).

          1 Reply Last reply Reply Quote 0
          • Gkikas LGPZG
            Gkikas LGPZ Moderator Meteorologist @ivo
            last edited by

            @ivo
            Maybe you refer to:
            If you read it (METAR), it's true. If you hear it (ATIS), it's magnetic.

            All charts and textual sources (METAR, TAF, winds aloft, surface analysis charts, etc) use true north as the reference.

            ATIS/AWOS/ASOS broadcasts, or any information a controller gives you over the radio, is magnetic.

            See:International Airport Example 1,
            here https://en.wikipedia.org/wiki/Automatic_terminal_information_service

            Gkikas LGPZG 1 Reply Last reply Reply Quote 2
            • Gkikas LGPZG
              Gkikas LGPZ Moderator Meteorologist @Gkikas LGPZ
              last edited by Gkikas LGPZ

              @ivo
              As the magnetic declination in Czech Rep. is 3~5 degrees and wind direction is given in tens of degrees, you have no problem!
              But if you fly to Greenland ....
              https://screenshots.firefox.com/kCNSJ4D19uIqOUNs/upload.wikimedia.org
              the ATC will give you wind dir. (for landing) in magnetic
              (also runways names (01 up to 36), refer to magnetic azimuth in tens of degrees).

              1 Reply Last reply Reply Quote 1
              • robertocosquinR
                robertocosquin
                last edited by

                No problem

                Roberto Mario Ramirez

                1 Reply Last reply Reply Quote 0
                • csabatatarC
                  csabatatar Moderator Pilot
                  last edited by

                  @ivo
                  I totally agree with @Gkikas-LGPZ .
                  The best mnemonic for it is: WRITTEN --> TRUE; SPOKEN --> MAGNETIC.

                  1 Reply Last reply Reply Quote 1
                  • R
                    regetr Meteorologist @ivo
                    last edited by

                    @ivo

                    from ICAO annex 3/chapter 4;

                    metar.PNG

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                    • waters mccartyW
                      waters mccarty @ivo
                      last edited by

                      True north is a fixed reference point based on the Earth's geographic poles. This consistency is crucial for aviation and maritime navigation, where precise wind direction information is essential for safe travel.
                      Magnetic north, influenced by the Earth's magnetic field, varies depending on location. Reporting in true north eliminates the need for constant adjustments based on location.

                      pixel speedrun

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                      • Mark henry 3M
                        Mark henry 3
                        last edited by

                        Apologies for the brevity! The term "True" in this context typically refers to the type of north indicated by a compass or navigation system that aligns with the Earth's geographic north pole. It contrasts with "magnetic north," which is the direction a compass needle points due to the Earth's magnetic field.

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