Pressure Measurement: Difference between revisions

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** In those sites following USA guidance, the SLP pressure is reported in the Remarks Group of the METAR.  There are METAR readers available that extract the SLP wherever it is within a METAR, but Saratoga does not.
** In those sites following USA guidance, the SLP pressure is reported in the Remarks Group of the METAR.  There are METAR readers available that extract the SLP wherever it is within a METAR, but Saratoga does not.
* A further complication is that QFE is defined in two ways:
* A further complication is that QFE is defined in two ways:
*# In USA, "Field elevation in pilot terms" is at a height equal to 10 feet above the mid point of main runway (a typical cockpit height) when reporting QFE. That reports 0.3 mBars above international standard.
*# In USA, ''Field elevation in pilot terms'' is at a height equal to 10 feet above the mid point of main runway (a typical cockpit height) when reporting QFE. That reports 0.3 mBars above international standard.
*# The international standard, used elsewhere in world, uses the airport (or runway) height (with no correction for height of cockpit) when reporting QFE
*# The international standard, used elsewhere in world, uses the true ''airport field elevation'' (i.e. runway height with no correction for height of cockpit) when reporting QFE.
* Finally, it should be noted that all METAR pressures in Pressure Group are rounded down to nearest mBar, so may read up to 0.9 mBar out from a reading expressed to nearest tenth of millibar.
* Finally, it should be noted that all METAR pressures in Pressure Group are rounded down to nearest mBar, so may read up to 0.9 mBar out from a reading expressed to nearest tenth of millibar.


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