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Reading and understanding a METAR

A METAR is an observation: it describes what was actually measured at an aerodrome at a particular time. Its structure is prescribed by law in Europe, which is why every piece of information always sits in the same place.

Applicability: European Union (EASA framework); provided in Germany by the Deutscher Wetterdienst (the national meteorological service)
Rulemaking authority: Commission Implementing Regulation (EU) 2017/373, Annex V (Part-MET), MET.TR.200 and MET.TR.205
Reviewed by NorthTrack on: 2026-09-13

What a METAR is

METAR is the routine aerodrome weather report. It is produced by an aeronautical meteorological station from observations and measurements. The Regulation requires a METAR to be filed for transmission no later than 5 minutes after the actual time of observation (MET.TR.200(c)). The report therefore describes a state, not a forecast.

Alongside the METAR there is the SPECI – a special report issued in addition when certain changes occur, for example the onset of freezing precipitation, or when the base of a cloud layer below 1,500 ft changes from SCT or less to BKN/OVC (MET.TR.200(e)).

The order of the elements

MET.TR.200(a) prescribes the order and it is binding. That is exactly what makes a METAR readable: you are not reading vocabulary, you are reading positions.

1
Element: Type of report · Example group: METAR, SPECI
2
Element: Location indicator · Example group: EDLW
3
Element: Time of the observation · Example group: 131020Z
4
Element: Identifier for an automated or missing report, where applicable · Example group: AUTO, NIL
5
Element: Surface wind: direction and speed · Example group: 24012G22KT
6
Element: Visibility · Example group: 6000
7
Element: Runway visual range (RVR), where the criteria are met · Example group: R24/1200
8
Element: Present weather · Example group: -RA
9
Element: Cloud (amount, height; type only for CB and TCU) or vertical visibility · Example group: BKN012
10
Element: Air temperature and dew-point temperature · Example group: 09/07
11
Element: QNH · Example group: Q1008
12
Element: Supplementary information, where applicable · Example group: WS R24

Order per MET.TR.200(a). QFE appears only in local reports; a METAR carries the QNH only (MET.TR.205(g)(4)).

The rounding rules – the part you really do need to know

The Regulation lays down not only what is reported but in what increments. Knowing the increments tells you immediately how precisely a figure is meant.

Visibility below 800 m
Reporting increment: in steps of 50 m · Reference: MET.TR.205(b)(1)
Visibility 800 m to below 5 km
Reporting increment: in steps of 100 m · Reference: MET.TR.205(b)(1)
Visibility 5 km to below 10 km
Reporting increment: in steps of 1 km · Reference: MET.TR.205(b)(1)
Visibility 10 km and above
Reporting increment: as 9999 or "10 km", otherwise CAVOK · Reference: MET.TR.205(b)(1)
RVR below 400 m
Reporting increment: in steps of 25 m · Reference: MET.TR.205(c)(1)(ii)
RVR 400–800 m
Reporting increment: in steps of 50 m · Reference: MET.TR.205(c)(1)(ii)
RVR above 800 m
Reporting increment: in steps of 100 m · Reference: MET.TR.205(c)(1)(ii)
Cloud base up to 10,000 ft
Reporting increment: in steps of 100 ft · Reference: MET.TR.205(e)(1)
Cloud base above 10,000 ft
Reporting increment: in steps of 1,000 ft · Reference: MET.TR.205(e)(1)
Temperature and dew point
Reporting increment: in whole degrees Celsius · Reference: MET.TR.205(f)(1)
QNH
Reporting increment: in whole hectopascals, four digits · Reference: MET.TR.205(g)(1)

Always rounded down
Observed values that do not fit the reporting increment are rounded down to the next lower step (MET.TR.205). A reported visibility of 1500 can therefore mean anything from 1,500 to 1,599 m. For the QNH the same rule works conservatively: a reported Q1008 may be as much as 1,008.9 hPa. Temperature is the exception – it is rounded to the nearest whole degree, with 0.5° going up.

The codes in the weather section

The weather group is built to a fixed pattern: intensity or proximity, then descriptor, then precipitation, obscuration or one of the remaining phenomena. At most three phenomena appear in one report.

Intensity and proximity

- — Light
An intensity marker, placed before the weather group.
(ohne Zeichen) — Moderate
With no sign in front of it, the phenomenon is moderate.
+ — Heavy
An intensity marker, placed before the weather group.
VC — Vicinity of the aerodrome
The phenomenon occurs in the vicinity, not at the aerodrome itself.

Descriptors

A descriptor never stands alone — with the exception of TS, when thunder has been heard but no precipitation observed.

MI — Shallow
A descriptor, for example MIFG — shallow fog.
BC — Patches
For example BCFG — fog patches.
PR — Partial
For example PRFG — the aerodrome is partially covered by fog.
DR — Low drifting
Driven below eye level, for example DRSN — low drifting snow.
BL — Blowing
Driven above eye level, for example BLSN — blowing snow.
SH — Shower
Always with a type of precipitation, for example SHRA — rain showers.
TS — Thunderstorm
With precipitation as TSRA; alone when thunder has been heard or lightning seen but no precipitation is falling at the aerodrome.
FZ — Freezing
Supercooled droplets, for example FZRA — freezing rain.

Precipitation

DZ — Drizzle
A type of precipitation.
RA — Rain
A type of precipitation.
SN — Snow
A type of precipitation.
SG — Snow grains
A type of precipitation.
PL — Ice pellets
A type of precipitation.
GR — Hail
Also appears in SIGMET phenomena, for example EMBD TSGR.
GS — Small hail / snow pellets
A type of precipitation.
UP — Unknown precipitation
Only in fully automatic reports.

Obscuration

BR — Mist
Visibility from 1,000 m to below 5,000 m with high humidity.
FG — Fog
Visibility below 1,000 m.
FU — Smoke
An obscuration.
VA — Volcanic ash
Also a SIGMET phenomenon in its own right (VA CLD).
DU — Widespread dust
Only in fully automatic reports.
SA — Sand
An obscuration.
HZ — Haze
An obscuration without high humidity.

Other phenomena

PO — Dust/sand whirls
Not reported in fully automatic reports.
SQ — Squall
A weather phenomenon in its own right.
FC — Funnel cloud / tornado
"Heavy" (+FC) stands for a tornado or a waterspout.
SS — Sandstorm
Also a SIGMET phenomenon, as HVY SS.
DS — Duststorm
Also a SIGMET phenomenon, as HVY DS.

Reading compound codes

Almost every weather code is a combination. The building blocks always come in the same order.

-SHRA = - (Light) + SH (Shower) + RA (Rain)
A light rain shower.

FZRA = FZ (Freezing) + RA (Rain)
Freezing rain — operationally one of the most critical codes there is.

BLSN = BL (Blowing) + SN (Snow)
Snow blown above eye level.

MIFG = MI (Shallow) + FG (Fog)
Shallow fog: ground fog you can see over the top of.

Cloud

The amount of cloud is given in eighths of the sky. Only two cloud types are named at all: CB and TCU.

FEW — Few
Cloud amount in eighths; does not form a ceiling.
SCT — Scattered
Does not form a ceiling.
BKN — Broken
From BKN upwards a ceiling exists.
OVC — Overcast
Forms a ceiling.
CB — Cumulonimbus
One of only two cloud types that are reported at all.
TCU — Towering cumulus
The precursor to cumulonimbus; the second reportable type.
NSC — Nil significant cloud
No cloud below 5,000 ft or below the highest minimum sector altitude, no CB and no TCU.
NCD — No clouds detected
Only in fully automatic reports.
VV — Vertical visibility
Takes the place of the cloud group when the sky cannot be discerned.

Qualifiers in the report

METAR — Meteorological Aerodrome Routine Report
An observation at an aerodrome; in Germany every half hour, at +20 and +50.
SPECI — Aviation selected special weather report
Issued in addition to the METAR on defined changes.
COR — Correct or corrected or correction
A correction made before the forecast period begins.
AUTO — Automatic
Marks a fully automatic METAR with no human observation.
NIL — None or I have nothing to send to you
The METAR or TAF was not produced.
CAVOK — Ceiling and visibility OK
Replaces visibility, RVR, weather and cloud — but only when all three conditions are met at the same time.
RVR — Runway visual range
Reported as long as either the visibility or the RVR is below 1,500 m.
VRB — Variable
The wind direction cannot be determined, or cannot be forecast.
Q — QNH in hectopascals
The QNH group in a METAR, for example Q1008.
A — QNH in inches of mercury
Customary outside Europe, for example A2992.
RE — Recent
Significant weather since the last observation but not at the time of it — for example RESN.
WS — Wind shear
Supplementary information in a METAR, for example WS R27 or WS ALL RWY.
RMK — Remark
The marker that national information follows.

CAVOK – what exactly is behind it

CAVOK replaces visibility, RVR, present weather and the entire cloud group. It may only be used when all three conditions in MET.TR.200(d) are met at the same time:

visibility of 10 km or more, and the lowest visibility is not being reported;
no cloud of operational significance;
no weather of significance to aviation.

CAVOK is therefore a statement about three things at once – not merely "good weather". Temperature, dew point and QNH still appear in the report.

Wind: when gusts are reported

Gusts appear as a group of their own when the peak speed exceeds the mean wind speed by 10 kt or more. Variation in direction is given as dddVddd. Wind of less than 1 kt is reported as calm; from 100 kt upwards it is reported as "more than 99 kt".

Example 1 – ordinary weather with wind, rain and several layers

A METAR with gusts, rain and a trend

METAR EDLW 131020Z 24012G22KT 210V270 6000 -RA BKN012 OVC020 09/07 Q1008 TEMPO 3000 RADZ BKN008

METAR — Routine aerodrome weather report (an observation).
EDLW — The aerodrome location indicator – Dortmund here.
131020Z — Observed on the 13th of the month at 10:20 UTC. Z always means UTC; aviation weather has no local time.
24012G22KT — Wind from 240° at 12 kt, gusting 22 kt. The gust is reported because it exceeds the mean speed by exactly 10 kt.
210V270 — The wind direction varied between 210° and 270°.
6000 — Prevailing visibility 6,000 m. Between 5 and 10 km the increment is one kilometre – which is why it reads 6000 and not 6300.
-RA — Light rain. - light, no sign moderate, + heavy.
BKN012 — Broken cloud (5–7 eighths) with a base 1,200 ft above aerodrome elevation.
OVC020 — Overcast (8 eighths) with a base at 2,000 ft.
09/07 — Temperature 9 °C, dew point 7 °C. The narrow 2 K spread fits rain and low cloud.
Q1008 — QNH 1,008 hPa, four digits and in whole hectopascals.
TEMPO 3000 RADZ BKN008 — Trend forecast: visibility 3,000 m at times, rain and drizzle, broken at 800 ft. A TREND is valid for 2 hours from the time of the report (MET.OR.225(c)).

A constructed teaching example. The location indicators are real ICAO indicators; the weather itself is invented. For an actual flight, only the current report from an official source applies.

Example 2 – CAVOK

A METAR with CAVOK

METAR EDDK 131350Z 32008KT CAVOK 18/06 Q1021 NOSIG

EDDK — Cologne/Bonn.
131350Z — 13th of the month, 13:50 UTC.
32008KT — Wind from 320° at 8 kt, no reportable gusts.
CAVOK — Visibility 10 km or more, no cloud of operational significance, no weather of significance – all three conditions at the same time.
18/06 — Temperature 18 °C, dew point 6 °C – a wide spread, dry air.
Q1021 — QNH 1,021 hPa.
NOSIG — Trend: no significant change expected in the next 2 hours.