A METAR, group by group

Free lesson · Meteorology · DGCA CPL and ATPL

A METAR looks like noise until you know the order. Every group, in the order it is written.

What does each group of a METAR mean?

A METAR, group by group

A model METAR, decoded one group at a time, in the order it is written. Tap Next.

  1. Who, where, when METAR is the routine weather report from an aerodrome, sent every half hour or hour. VIDP is the ICAO code for Delhi. 200700Z: the 20th of the month at 0700 UTC ("Zulu"). Add 5 h 30 min for Indian time: 1230 IST.
  2. Wind 11007G20KT: from 110° true at 7 kt, gusting to 20 kt. A gust is reported when it is 10 kt or more above the mean. 090V160: the direction keeps changing between 090° and 160°.
  3. Visibility 1400: the prevailing visibility is 1400 m, how far you can see over most of the area round the aerodrome. 9999 means 10 km or more. At 1400 m a pilot sees the ground only a short way ahead, so this is a poor day. Below 1500 m the report must also give the RVR, the next group.
  4. RVR R28/1100: the runway visual range on runway 28 is 1100 m. It is given only when the visibility or the RVR is below 1500 m.
  5. Weather +SHRA: heavy (+) showers (SH) of rain (RA). A minus sign means light; no sign means moderate.
  6. Cloud Amount in octas (FEW 1-2, SCT 3-4, BKN 5-7, OVC 8), then the base in hundreds of feet above the aerodrome: SCT010 is 3-4 octas at 1000 ft. CB (or TCU) is added after the height. Careful: this model breaks a rule. After a BKN layer, a higher layer is reported only if it is BKN or OVC, so FEW030 could not appear there.
  7. Temperature / dew point 33/26: air 33 °C, dew point 26 °C. Below zero the figure takes an M for minus: 10/M02.
  8. QNH Q1008: QNH 1008 hPa. It is always rounded down and always has four figures (Q0996). In inches it would be written A2992.
  9. TREND NOSIG: no significant change expected in the next 2 hours. The = marks the end of the report.

Memory hook: Who-where-when · wind · vis · RVR · wx · cloud · T/Td · Q · trend.

Takeaway: A METAR always runs in the same order: type, station, date and time (UTC), wind, visibility, RVR, weather, cloud, temperature/dew point, QNH, then any extras (RE recent weather, WS wind shear) and the TREND.

In what order are the groups written?

The order

Fly along a METAR, group by group, the way the teacher splits it.

  1. Type METAR or SPECI Routine report, or special report between routine ones.
  2. Station VIDP ICAO four-letter code: VIDP Delhi, VABB Mumbai, VECC Kolkata, VOMM Chennai.
  3. Day and time 200700Z Day of the month and UTC. Add 5 h 30 min for IST: 0700Z is 1230 IST.
  4. Wind 11007G20KT 090V160 Direction (true) and speed, gusts, and the extremes of a varying direction.
  5. Visibility 1400 In metres. 9999 = 10 km or more.
  6. RVR R28/1100 Only when the visibility or RVR is below 1500 m.
  7. Weather +SHRA Intensity, descriptor, phenomenon.
  8. Cloud SCT010 BKN020 Amount and base in hundreds of feet above the aerodrome. Or VV, NSC, SKC.
  9. Temp / dew point 33/26 Whole °C; M for minus.
  10. QNH Q1008 Rounded down to a whole hPa.
  11. Extras RETS, WS RWY28 Recent weather and wind shear.
  12. TREND NOSIG, TEMPO, BECMG The landing forecast for the next 2 hours. Then = ends the report.

Takeaway: Type · station · time · wind · visibility · RVR · weather · cloud · T/Td · QNH · RE · WS · TREND.