METAR

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Decoded METAR messages for airfields in Switzerland

METAR is a standardized message in short form that shows the weather observation of a single airfield.

METAR was originally the abbreviation for French. Message d'observation météorologique régulière pour l'aviation or MÉTéorologique Aviation Régulière . In English, the formulations MET eorological A erodrome R eport , Aviation Routine Weather Report or Meteorological Aviation Routine Weather Report are common.

A METAR always contains the ICAO code of the aerodrome that created this METAR and the time of observation. In addition, wind direction , visibility , temperature , air pressure , cloud formation and other information can be included. Military aviation pursues similar objectives with pre-flight weather intelligence as part of so-called weather flights .

See

Basic structure of a METAR message

There are several providers on the Internet whose websites you can call up reports from all stations in the world, including those from the German Weather Service or the US National Oceanic and Atmospheric Administration (NOAA). An example METAR looks like this:

EDDS 081620Z 29010KT 9999 FEW040TCU 09 / M03 Q1012 NOSIG

The individual groups have the following meaning:

  • EDDS = airport identifier, here Stuttgart airport
  • 081620Z = observation time (08th of the month at 16:20 UTC, i.e. 17:20 CET or 18:20 CEST)
  • 29010KT = wind direction related to true north (290 °, i.e. WNW) and wind speed (10  kn )
  • 9999 = visibility on the ground in m (here 10 km or more) → Not to be confused with runway visibility ( RVR )!
  • FEW040TCU = Cloud cover: thickness (FEW = 1 to 2 eighths), height of the cloud base (4,000 feet above ground) and type of cloud cover (e.g. TCU = towering cumulus)
  • 09 / M03 = temperature (9 ° C) and dew point (M stands for negative values, i.e. −3 ° C)
  • Q1012 = QNH of 1012 hPa, i.e. the air pressure prevailing on the site according to the standard atmosphere reduced to sea level is 1012 hectopascals
  • NOSIG = (" no sig nificant change") forecast for the next two hours

Sometimes there is the word "AUTO" between the time stamp and the wind information. Then the METAR was generated fully automatically by the measuring station and without human control.

Update

METAR reports from civil German airfields are updated every 30 minutes or when the weather changes significantly (at 20 minutes and 50 minutes past the hour and can be heard as part of the ATIS , e.g. at 1:20 p.m. and 1:50 p.m. etc.) . The METAR updates are not uniform internationally. The update time and interval can therefore differ.

Detailed explanations

Wind information

example Explanation
29010KT Wind direction 290 °, 10 kt
00000KT Calm
29010G30KT Wind direction 290 °, 10 kt; in gusts (English: g usts) 30 kt
VRB03KT Variable wind direction, 3 kt
29010KT 210V310 mean wind direction 290 °, turns between (variation) 210 ° and 310 °, 10 kt; Specification of the variation only with> 60 ° deviation

At Russian airports, the wind speed is stated in meters per second (29003MPS).

view

The visibility on the ground is given in four digits in meters:

example Explanation
5000 Visibility 5000 m
9999 Visibility 10 km or more

From a visibility of 5 km, the visibility is only given in 1000 meter increments, whereby the visibility is always given rounded.

This information is not direction-specific! If the visibility for the slopes is to be specified ( Runway Visual Range = RVR, for visibility below 1500 m), the following group is used, for example: R27L / 1200U , i.e. In other words, there is a visibility of 1200 m on runway 27L, and the trend is rising. The last letter indicates the change tendency of the last 10 minutes: U = upward (rising), D = downward (falling), N = no distinct tendency (constant).

With a clear view and clear weather conditions, CAVOK (clouds and visibility OK) is reported instead of the visibility and cloud values . The following conditions must be met:

  • prevailing minimum visibility of 10 km or more
  • no clouds below 5000 ft or below the highest sector minimum altitude
  • no CB / TCU
  • no weather phenomenon (according to table: weather).

Special weather phenomena

The abbreviations in the table below are based partly on the English and partly on the French term. The German equivalent is also listed. If necessary, special weather phenomena are reported according to the following rules:

Weather (FMH-1 HANDBOOK and DWD "METAR / TAF weather key for aviation")
QUALIFIER
(trait) 		WEATHER PHENOMENA
(weather phenomena)

INTENSITY OR PROXIMITY
(intensity or proximity)

DESCRIPTOR
(descriptor) 		PRECIPITATION
(type of precipitation) 		OBSCURATION
(cloudiness) 		OTHER
(other)
 -
  • light
  • weak
  • faible
 
  • moderate
  • moderate (see note 2)
  • modéré
 +
  • heavy
  • strong
  • forte
VC
  • in the v i c inity
  • nearby (see note 4)
  • au voisinage
RE
  • re cent
  • recently
  • récent
MI
  • shallow
  • flat
  • mi nce
PR
  • partial
  • in places
  • p a r tiel
BC
  • patches
  • individual swaths
  • b an c s
DR
  • low dr ifting
  • sweeping
  • chasse basse
BL
  • bl owing
  • impulsive
  • chasse élevée
SH
TS
FZ
WS
Double room
  • D ri z zle
  • drizzle
  • Bruine
RA
SN
  • Sn ow
  • snow
  • Running out
SG
  • S now g rains
  • Snow pebbles
  • Neige en grains
IC
PL
GR
GS
  • Small hail and / or snow pellets
  • Ripe / frost sleet
  • G ré s il
UP
  • U Nknown P recipitation
  • Indefinite rainfall
  • Précipitation inconnue
BR
  • Damn
  • damp haze
  • Br ume
FG
  • F o g
  • fog
  • Brouillard
FU
VA
YOU
  • Widespread you st
  • spreads dust
  • Poussière généralisée
SA
  • Sa nd
  • sand
  • Sable
HZ
  • H a z e
  • dry haze
  • Brume sèche
PY
  • S p ra y
  • Spray mist / spray
  • Fumée d'eau
PO
SQ
  • Sq ualls
  • Gusts
  • Lignes de grains
FC
  • F unnel c loud (s) (tornado or waterspout)
  • Trombe / Windhose (with water: + FC) (see note 3)
  • Trombe terrestre ou marine
SS
DS
  • D ust s torm
  • Dust storm
  • Tempete de poussière
  1. Weather codes should be structured in the appropriate order, taking into account columns 1 to 5 of the table above, i.e. H. Intensity, followed by the descriptor, followed by the weather phenomenon, e.g. B. heavy rain showers is coded as + SHRA.
  2. To indicate moderate intensity, no entry or symbol is placed in front.
  3. Tornadoes and waterspouts should be coded as + FC.
  4. The location of weather phenomena should be reported as “nearby” if they are between 5 and 10 miles from the observation point (s). In Germany: Within 8 km, but not at the airport

Cloud cover

The height of the cloud base is transmitted in hundreds of feet above ground and simulated according to the cloud condition. This is coded as follows:

abbreviation Complete name Explanation
NSC N il S ignificant C loud No cloud cover below 1524 m (5000  ft ) or below the minimum sector height and no thunderclouds (CB, TCU) unless conditions for CAVOK are met ( SKC Sky Clear has been abolished)
NCD N o C louds D etected no cloud registered or no cloud heights measured; only takes place with automatic stations
CAVOK C Eiling, Clouds a nd V isibility OK
  • No clouds below 1524 m (5000  ft ) above ground or, if this is higher, below the Minimum Sector Altitude (MSA)
  • No thunderclouds (CB, TCU)
  • Visibility over 10 km
  • no significant weather phenomenon
FEW Apartment 1 to 2 eighths
SCT Sc a t tered 3 to 4 eighths
BKN B ro k e n 5 to 7 eighths
OVC Ov er c ast 8 eighths (overcast sky)

Other common abbreviations for cloudiness are:

abbreviation Complete name Explanation
CLR Cl ea r 0 eighth clouds below 12000 ft (measured by automatic stations)

The cloud type can be added if necessary:

abbreviation Explanation
TCU T owering Cu mulus
CB C umulonim b us

Air pressure

The air pressure is always given in four digits. The unit used is either hectopascals (hPa) or hundredths of an inch of mercury (inHg). The pressure information refers to the pressure at sea level, calculated from the pressure at the site, assuming the conditions of the standard atmosphere ( QNH ). There is a Q before the pressure indication of QNH in hectopascal is specified, is an A for altimeter (Altimeter) against the unity hundredths of inches of mercury is in the US (in use).

specification QNH
Q1038 1038 hPa
A3020 30.20 inHg

Color code

Military stations in Europe usually use a color code at the end, or also called a color state, which contains the main cloud base and the horizontal visibility:

Visibility / main cloud base <0.8 km 0.8 - <1.6 km 1.6 - <3.7 km 3.7 - <5 km 5 - <8 km ≥ 8 km
≥ 20,000 ft RED AMB YLO GRN WHT BLU +
2500 - <20000 ft RED AMB YLO GRN WHT BLU
1500 - <2500 ft RED AMB YLO GRN WHT WHT
700 - <1500 ft RED AMB YLO GRN GRN GRN
300 - <700 ft RED AMB YLO YLO YLO YLO
200 - <300 ft RED AMB AMB AMB AMB AMB
<200 ft RED RED RED RED RED RED

The code BLACK means that the runway cannot be used for reasons other than falling below the visual range or the lower limit of the main cloud. It is placed in front of the actual color code.

trend

code Explanation
NOSIG NO SIGNIFICANT CHANGE - no significant weather change expected within the next 2 hours
BECMG BECOMING - there follows a change in the basic weather
TEMPO TEMPORARY - there are temporary fluctuations, in individual cases less than an hour, in total less than half of the forecast period

Other weather reports

In addition to the METAR exists the Terminal Aerodrome Forecast (TAF) , the weather forecast or which contains G eneral A viation For eCast ( GAFOR ).

See also

Web links

Individual evidence

  1. ↑ FEDERAL METEOROLOGICAL HANDBOOK No. 1 Surface Weather Observations and Reports. (PDF; 951 KB) Accessed March 1, 2019 (English).
  2. ↑ METAR / TAF weather key for aviation. (PDF; 2.7 MB) German Weather Service , accessed on March 1, 2019 .