UNDERSTANDING METAR

This lesson will explain the Meteorological Terminal Air Report or METAR and how to read and decode it. METARS published in the UK at 20 past and 50 past each hour. The general format of a METAR is as follows.

    1. Identification
    2. Wind
    3. Visibility
    4. RVR
    5. Present Weather
    6. Cloud
    7. CAVOK
    8. Temperature and Dew point
    9. QNH
    10.  Recent Weather
    11. Wind Shear
    12. Colour State
    13. Trend

1: Identification is made up of 3 parts

EGNMLeeds Bradford
06Date
1620ZTime
AUTOA fully automated report with no human intervention

EGNM 061620Z 26010G25KT 200V300 R14/800D FG -RA BKN018TCU 10/02 RE+RA WS RWY 14 BECMG SCT039 FEW022

2: Wind

260Wind Direction (Coming from)
10KTSpeed 10 Knots
G25KTGusting 25 Knots
200V300The direction of wind varies between 200 degrees and 300 degrees
CALMThe wind is calm 00000KT

EGNM 061620Z 26010G25KT 200V300 3000 1300SW R14/800D FG -RA BKN018TCU 10/02 RE+RA WS RWY 14 BECMG SCT039 FEW022

3: Visibility is depicted in Metres.

0000Less than 50 metres999910 kilometres or more
3000Visibility 3000M
1300SW Visibility to SW 1300M

You may also see 1300SW indicating that the minimum visibility to the SW is 1300 metres.

EGNM 061620Z 26010G25KT 200V300 3000 1300SW R14/800D FG -RA BKN018TCU 10/02 RE+RA WS RWY 14 BECMG SCT039 FEW022

4: RVR , Runway Visual Range is the range over which the pilot of an aircraft on the centre line of a runway can see the runway surface markings or the lights delineating the runway or identifying its centre line. This is displayed with the runway first and then the visibility R14 – Runway 14 and then this visible distance shown in metres 800.

UIncreasingDDecreasingNNo change (Not reported in the UK at Present)

These may be added to the figure R14/800D
R14/800

EGNM 061620Z 26010G25KT 200V300 3000 1300SW R14/800D FG -RA BKN018TCU 10/02 RE+RA WS RWY 14 BECMG SCT039 FEW022

5: Present weather is shown in codes for example RA is rain -RA is light rain +RA is heavy rain.

Present Weather
– LightNo qualifier = Moderate+ Heavy
BCPatchesBLBlowingBRMist
DSDust StormDUDustDZDrizzle
FCFunnel cloudFGFogFUSmoke
FZFreezingGRHail>5mmGSSmall Hail
HZ HazeICIce CrystalsMIShallow
PLIce PelletsPODust DevilsPRBanks
RARainSASandSHShowers
SGSnow GrainsSNSnowSQSqualls
SSSand StormsTSThunderstormsUPUnidentified
PrecipitationAuto Only
VAVolcanic AshVCIn vicinity  

EGNM 061620Z 26010G25KT 200V300 3000 1300SW R14/800D FG -RA BKN018TCU 10/02 RE+RA WS RWY 14 BECMG SCT039 FEW022

6: The scale on which cloud cover is observed is called Oktas scale which goes from 0 to 8.

0Clear
1-2FEWFew
3-4SCTScattered
5-7BKNBroken
8OVCOvercast
TCUTowering CumulusCBcumulonimbusVV003state of the sky obscuredIn lieu of figuresEach / represents 100ft up to 3

Cloud height is given in ft above the airfield height.

FEW021 SCT039
or
VV008

EGNM 061620Z 26010G25KT 200V300 3000 1300SW R14/800D FG -RA BKN018TCU 10/02 RE+RA WS RWY 14 BECMG SCT039 FEW022

7: CAVOK cav-oh-kay. Visibility greater or equal to 10 km and the lowest visibility is not reported, no cumulonimbus or towering cumulus, no cloud below 5000 ft or highest MSA (greater) and no weather significant to aviation.

8: The first digits are the temperature after the / is the dew point, the dew point is the temperature to which it must be cooled to become saturated with water vapour.

EGNM 061620Z 26010G25KT 200V300 3000 1300SW R14/800D FG -RA BKN018TCU 10/02 RE+RA WS RWY 14 BECMG SCT039 FEW022

9: QNH the altimeter setting.

Most METAR stops at this point, you may see some of the following.

10: Since 5 is present weather recent weather gives you a short look into the past, you may see something like RETS indicating a recent thunderstorm which would mean the runway is more than likely wet. Up to 3 groups may be present.

EGNM 061620Z 26010G25KT 200V300 3000 1300SW R14/800D FG -RA BKN018TCU 10/02 RE+RA WS RWY 14 BECMG SCT039 FEW022

11: Wind shear is defined as a wind direction and/or speed change over a vertical or horizontal distance. This could result in you losing airspeed rapidly.

EGNM 061620Z 26010G25KT 200V300 3000 1300SW R14/800D FG -RA BKN018TCU 10/02 RE+RA WS RWY 14 BECMG SCT039 FEW022

12: Colour state Military reports also display a colour state BLU, WHT, GRN, YLO, AMB or RED, coded according to cloud and visibility. BLACK may also be reported when the runway is unusable.

13: Trend

BECMGBecomingNSWNo sig weather
TLUntilTEMPOTemporarily
ATAtNSCNo sig cloud
NOSIGNo sig changeFMFrom

EGNM 061620Z 26010G25KT 200V300 3000 1300SW R14/800D FG -RA BKN018TCU 10/02 RE+RA WS RWY 14 BECMG SCT039 FEW022

The example above is a fake METAR to include as many options as possible for demonstration purposes.

METAR EGNM 071050Z 26019G31KT 9999 SCT035 13/04 Q1015

You can see it’s much simpler.