Altimeter setting as reported in a METAR or SPECI. US stations report in inches of mercury (A group), ICAO stations report in hectopascals (Q group). Some reports may include both.
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Altimeter setting in hectopascals / millibars (ICAO Q group, e.g. Q1013 = 1013 hPa).
Altimeter setting in inches of mercury (US A group, e.g. A2992 = 29.92 inHg).
Altimeter setting as reported in a METAR or SPECI. US stations report in inches of mercury (A group), ICAO stations report in hectopascals (Q group). Some reports may include both.