METAR & TAF REPORTS




DATE: Tuesday, July 23, 2019 (12:22 UTC )
METAR (Aerodrome Report)

METAR or Aviation Routine Weather Reports is a standard for transmitting weather reports from airfields. The content of this report includes:

  • Station Location CCCC - This represents the four-letter ICAO identifier where the weather was observed.
  • Observation Time DDhhmmZ - The UTC time the observation was taken where (DD) is the calendar day, (hh) is the hour, and (mm) is the minute.(Z) stands for Zulu or UTC time.
  • Auto Flag AUTO - indicates that the observation came from automatic station or machine.
  • Surface Wind dddff - The wind direction in degrees (ddd) and wind speed (ff). If the winds are gusting, the format will be (dddffGgg) where gg is the gust speed. The groupis always appended with the speed units: KT (konts) MPS (meter per seconds) or KMH (kilometers per hour). If the wind direction will be variable, ddd is encoded as VRB. Calm winds (3 knots or less) are encoded as 00000KT.
  • Prevaling Visibility PV - Aerodrome visibility, defined as the greatest distance at which an object can be seen. When the visibility varies in different directions, the lowest visibility is used. Always ends with (SM) statute miles or nothing if (m) meters.
  • Runway Visual Range (if required) RVR - Defined as the distance over which a pilot of an aircraft on the centreline of the runway can see the runway surface markings delineating the runway or identifying its centre line (wikipedia). RVR is usually reported in meters.
  • Weather ww - A two letter standard abbreviation (see Table 1. below) for the current weather appearing at the station. The term CAVOK (Ceiling and Visibility OK) replaces visibility, weather and cloud when the following conditions are met: a.) visibility is greater than or equal to 10km and there's no cloud below 5000ft (1500m) b.) No CB or Cumulonimbus cloud present, No precipitation or any other weather such as SS, FG, etc.
  • Cloud Condition CCCHHH - Assigned for each layer of cloud. Consists of Cloud amount or cloud cover (CCC) and height in hundreds of feet (HHH) see Table 2. for descriptors. The term NSC (Nil or No Significant Cloud) is used when there's no cloud and CAVOK is not appropriate. When the sky is obscured and cloud details cannot be assessed, (CCC) will be encoded as VV for Vertical Visibility and the (HHH) value will indicate the visibility into the obscuration.
  • Temperature/Dewpoint tt/td - Then temperature (tt) and dewpoint in degrees Celsius. If values are negative, it is preceded by an (M).
  • Pressure P - This starts with (Q) which indicates sea-level pressure with the value in whole millibars (mB).
  • Pressure in Inches A - This starts with (A) which indicates altimeter setting with the value in hundreds of inches.
  • Remarks RMK - It indicates any supplementary information.
  • End of message = - Equal (=) sign should be appended at the end to indicate the end of message.

Example #1 Example METAR collectives

METAR OMAA 020100Z 11002KT 0400 R13/0650 R31/0375 FG VV/// 15/14 Q1012 A2989=

METAR OMDB 180800Z 32004KT 280V010 CAVOK 37/08 Q1010 A2983=

METAR OOMS 140700Z VRB03KT 8000 NSC 36/17 Q1009 NOSIG=

METAR OEDF 051100Z 04020G30KT 7000 SCT045 29/14 Q1009 NOSIG=

METAR OTDB 051100Z 04010KT 9999 SCT030 FEW040CB SCT100 30/22 Q1008=

TAF (Aerodrome Forecast)

TAF or Terminal Aerodrome Forecast is a worldwide standard for encoding weather forecast for any airport. It is based on METAR observation format. The content of this report includes:

  • Station Location CCCC - This represents the four-letter ICAO identifier where the forecast weather will occur.
  • Issuance Time DDhhmmZ - The UTC time the forecast was issued, where (DD) is the calendar day, (hh) is the hour, and (mm) is the minute. (Z) stands for Zulu or UTC time.
  • Forecast or Validity Period DDHHEE - The UTC time of the the forecast period, where (DD) is the calendar day followed by two-digit beginning hour (HH) then two-digit ending hour (EE) usually on the next day. TAFs are valid for 30 hours and are issued evert 6 hours.
  • Meteorological Conditions Wind » Visibility » Weather » Clouds » Optional data(Wind Shear) - This is the body of the message. Wind, visibility, weather, and clouds or sky condition are part of the initial group forecast. Weather is included only in the initial group when it is significant to aviation. The coding for this group is the same as METAR message. Wind Shear is entered after the sky condition when wind shear is expected. The general format for this would be (WShhh/dddff) where (hhh) is the height of the wind shear followed by wind direction (ddd) and wind speed (ff) at the indicated height.
  • Transition Identifiers - New groups of weather conditions that will occur. Includes:

  • » FROM Group FM hhmm - indicates a significant change will take place at hour (hh) and minute (mm).

    » TEMPO Group TEMPO hhee - indicates a temporary condition (less than half the period) changes in weather between hour (hh) and (ee) hours.

    » BECMG Group BECMG hhee - indicates a gradual change in weather between between hour (hh) and (ee) hours.

    » PROB Group PROBpp hhee - indicates a temporary condition with a probability value (pp) percent between (hh) and (ee) hours.
  • End of message = - Equal (=) sign should be appended at the end to indicate the end of message.

Example #1 Example TAF for OMAA

TAF OMAA 140500Z 1406/1512 17006KT 8000 FEW030
   BECMG 1406/1408 35012KT
   BECMG 1415/1417 24006KT
   TEMPO 1500/1504 VRB03KT 4000 HZ BKN006
   BECMG 1505/1507 33012KT=

TAF OMAL 200500Z 2006/2112 30014KT 7000 NSC
   PROB40 2008/2011 32018G28KT 3000 BLDU
   BECMG 2016/2018 23005KT
   PROB30 2101/2103 4000 HZ
   BECMG 2108/2110 30012KT=

*Updated: 21/05/2017