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METAR and TAF in European format: a step-by-step decoder

It is six in the morning, you want to fly a few circuits and you are looking at a line like this: BKN008 TEMPO 2500 -RA. Most guides online are American, full of inches of mercury and statute miles. Here we read the format European aerodromes actually use, group by group, and at the end you decide for yourself whether you go.

  • Student pilot
  • EASA 050 · Meteorology
  • EASA 010 · Air Law
  • 12 min read
  • 19 October 2026

The problem

METAR

METAR LROP 191230Z 25012G24KT 210V280 6000 -SHRA FEW020 BKN035 14/09 Q1012 TEMPO 3000 SHRA

A METAR is a snapshot of the weather at an aerodrome, usually taken every 30 minutes at big airports and every hour at smaller ones. A TAF is the forecast for the same aerodrome over the next hours. Both use an international code set by ICAO and the World Meteorological Organization, with small national differences.

The popular guides are written for American pilots: visibility in statute miles, pressure in inches of mercury, no CAVOK. In Europe you see metres, hectopascals and groups an American guide never mentions. That is what you learn in subject 050 Meteorology for the PPL, and what you read every morning at the briefing.

Anatomy of a METAR

A METAR always comes in the same order. Once you know the order, each group tells you what it is by its shape.

METARLROP191230Z25012G24KT210V2806000-SHRAFEW020BKN03514/09Q1012TEMPO 3000 SHRA
  • IDtype, aerodrome, day and time UTC
  • winddirection, speed, gusts
  • visvisibility, RVR
  • wxweather: rain, fog…
  • cloudamount and base
  • T/Tdtemperature and dew point
  • QQNH in hPa
  • trendthe next 2 hours
The same METAR, coloured by type of group. The decoder below uses the same colours.

1. Who, where, when

METAR is the routine report. If the weather changes significantly between two reports, a SPECI, a special report, comes out. LROP is the ICAO code of the aerodrome (Bucharest Otopeni). 191230Z means day 19 of the month, 12:30 UTC. The Z stands for "Zulu", which is UTC: in summer, local time in Romania is UTC + 3.

2. Wind

25012G24KT: wind from 250°, 12 kt, gusting 24 kt. The speed is the mean over the last 10 minutes, and gusts are reported when the peaks exceed that mean by 10 knots or more. 210V280 shows that the direction varied between 210° and 280°. VRB03KT is a light wind of variable direction, and 00000KT is calm.

Watch out

METAR and TAF winds are given from true north. Runways and the ATIS or tower wind are magnetic. In much of Europe the difference is a few degrees, but for an exact crosswind see the crosswind article.

3. Visibility

In Europe visibility is in metres, four digits: 6000 is 6 km, and 9999 means 10 km or more (not "unlimited"). If it is much worse in one direction, the minimum is added with its direction: 6000 1400SW. When fog brings visibility right down, the runway visual range appears too: R26L/0450U means 450 m on runway 26L, improving (U). D means getting worse, N no change.

4. Weather

A weather group has up to three parts: intensity, a descriptor and the phenomenon itself. -SHRA reads "light, showers, rain": light rain showers. No sign means moderate; + means heavy. VC means in the vicinity, roughly 8–16 km away but not at the aerodrome.

DescriptorsPrecipitationReduced visibility
SH showers · TS thunderstormRA rain · DZ drizzleFG fog (under 1,000 m)
FZ freezing · BL blowingSN snow · GR hailBR mist (1,000–5,000 m)
MI shallow · BC patchesGS small hail · PL ice pelletsHZ haze · FU smoke

Combinations you will see often: TSRA thunderstorm with rain, FZFG freezing fog, BCFG fog patches, VCSH showers in the vicinity.

5. Cloud

Each cloud layer gives its amount, in eighths of the sky, and the height of its base in hundreds of feet above the aerodrome, not above sea level. BKN035 means broken cloud with its base at 3,500 ft.

CodeMeansEighths of sky
FEWfew1–2
SCTscattered3–4
BKNbroken5–7
OVCovercast8

The only cloud types ever named are the dangerous ones: CB, the thunderstorm cumulonimbus, and TCU, towering cumulus that can turn into a shower. VV002 means the sky cannot be seen at all (usually in fog) and vertical visibility is 200 ft. NSC means no significant cloud, and NCD appears from automatic stations that detected no cloud.

The ceiling is the base of the lowest layer covering more than half the sky: the first BKN or OVC (or the vertical visibility when the sky is hidden). In the example, FEW020 does not count and the ceiling is 3,500 ft. The ceiling is the number you compare with the VFR minima.

6. CAVOK

CAVOK ("cav-oh-kay") replaces visibility, weather and cloud when all of these hold: visibility 10 km or more, no cloud below 5,000 ft or below the highest minimum sector altitude (whichever is greater), no CB or TCU, and no significant weather. CAVOK does not mean a clear sky: there may be cloud at 6,000 ft. Near mountains, where the sector altitude is high, CAVOK tells you about the aerodrome, not about the ridge you plan to cross.

7. Temperature, dew point and QNH

14/09: temperature 14 °C, dew point 9 °C. Negative values carry an M: M02/M04. When the two come within a degree or two, the air is close to saturation and mist or fog is not far away. Q1012 is the QNH in hectopascals: set it on the altimeter and you read altitude above sea level. If you see A2992, it is an American report, in inches of mercury.

8. Supplementary groups and the trend

RE marks recent weather that has ended or eased since the last report: RETS means there was a thunderstorm. WS R27 reports windshear on runway 27. At many European aerodromes a trend follows, a short forecast valid for 2 hours: NOSIG (no significant change), BECMG (becoming) or TEMPO (temporarily). In our example, TEMPO 3000 SHRA says that over the next two hours visibility may drop for short spells to 3 km in showers.

How to read a TAF

TAF

TAF LRCL 190500Z 1906/2006 13006KT 6000 BKN015 TEMPO 1906/1909 2500 -RA BKN008 FM191200 30012KT 9999 FEW040 PROB40 2002/2006 0800 FG

The start looks like a METAR: LRCL (Cluj), issued on the 19th at 05:00 UTC, and 1906/2006 is the validity: from day 19 at 06 to day 20 at 06 UTC. Small aerodromes usually get 9-hour TAFs, big ones 24 or 30 hours. Then comes the main forecast (wind, visibility, cloud), followed by change groups, each with its own period.

GroupWhat it means
FM191200From the time given, a new, complete forecast replaces the previous one.
BECMG 1918/1920Conditions change gradually at some point in the period (normally 2 hours at most) and stay that way.
TEMPO 1906/1909Temporary fluctuations: each lasts under an hour and, added up, less than half of the period.
PROB30 / PROB40A 30 % or 40 % probability of what follows. Can be combined with TEMPO.
TEMPO BECMG FM VFR CTR: 5 km 10 km 5 0 12Z 15Z 18Z 21Z 24Z forecast visibility
Three kinds of change. TEMPO: visibility dips briefly and comes back. BECMG: it drops gradually and stays down. FM: everything changes at once, at the time given.

In the Cluj example: in the morning, between 06 and 09 UTC, there may be spells of light rain, 2.5 km visibility and a ceiling of 800 ft. From 12 UTC the wind turns to 300° and the sky clears. Towards the next morning, between 02 and 06 UTC, there is a 40 % chance of fog with 800 m visibility.

Planning rule

If your departure or arrival time falls inside a TEMPO or a PROB, plan for the worst conditions in that group. In a BECMG, assume a change for the worse arrives at the start of the period, and a change for the better only at its end.

Ceiling and the VFR check, as pseudocode

The decoder below does exactly what you would do on paper: find the first BKN or OVC layer, compare it and the visibility with the minima, then repeat for every change group.

Pseudocodeceiling and VFR
function ceiling(cloud_groups):
    ceiling = none                      # FEW and SCT never make a ceiling
    for g in cloud_groups:
        if g.code in [BKN, OVC, VV] and g.base < ceiling:
            ceiling = g.base               # hundreds of ft above the aerodrome
    return ceiling

function vfr_in_ctr(visibility_m, ceiling_ft):
    if visibility_m >= 5000 and ceiling_ft >= 1500: return "VFR possible"
    if visibility_m >= 1500 and ceiling_ft >= 600:  return "special VFR only"
    return "below special VFR"

# TAF: run it on the main forecast and on each BECMG / TEMPO / PROB / FM

Try it yourself

Paste a real METAR or TAF from your aviation weather service or briefing app, or pick an example. Tap a coloured group to jump to its explanation. Everything runs in the page; nothing is sent anywhere.

The VFR decision: go or no go?

For take-off, landing and circuits in a control zone (CTR), the European SERA rules require, without a special clearance, a ceiling of at least 1,500 ft and a ground visibility of at least 5 km. Below that, the tower can give a special VFR clearance, but only with a ceiling of at least 600 ft and a ground visibility of at least 1,500 m. You then fly clear of cloud, with the surface in sight and at 140 kt or less.

In a CTRGround visibilityCeiling
VFR (SERA.5005(b))≥ 5 km≥ 1,500 ft
Special VFR (SERA.5010)≥ 1,500 m≥ 600 ft

These are the legal minima, not good minima for a student. Your school has its own, and you should have personal minima above them, especially for your first solo flights. Some things the minima do not cover at all: CBs and thunderstorms (you go around them, never underneath), strong gusts, and a crosswind beyond what was demonstrated for your aircraft.

Common traps

Heights are above the aerodrome

BKN015 means 1,500 ft above the runway. If your route crosses hills 1,000 ft higher than the aerodrome, the cloud there may be only 500 ft above the ground.

The METAR is already old

A METAR from 12:30 describes 12:30. For what comes next, read the trend and the TAF. When the weather is turning quickly, look for a SPECI or listen to the ATIS.

TEMPO is not "maybe"

A TEMPO is not a mere possibility: the forecaster expects those conditions to happen, just not for long. If a TEMPO with an 800 ft ceiling covers your arrival time, your arrival cannot be planned VFR.

9999 is not infinite, CAVOK is not clear sky

9999 means "at least 10 km". CAVOK still allows cloud above 5,000 ft or the sector altitude. Both are good news, but they do not mean there is nothing left to check.

American reports

If you fly outside Europe or use an American app, you may see 10SM (statute miles), A3012 (inches of mercury) and an RMK section at the end. The decoder recognises them and converts them roughly.

Check yourself: 10 reports

For each one, decide whether you can fly VFR circuits in a CTR at the time of the report or at the time given. These examples were written for practice and are not real reports.

1. METAR LRBV 191200Z 09008KT 9999 SCT045 BKN100 16/04 Q1021 NOSIG

VFR possible. Visibility at least 10 km, the ceiling is BKN at 10,000 ft (SCT045 does not make a ceiling), and no change is expected for 2 hours.

2. METAR LRTM 190700Z 00000KT 3500 BR BKN009 06/05 Q1024

Special VFR only. 3.5 km and a 900 ft ceiling are below 5 km and 1,500 ft, but above 1,500 m and 600 ft. As a student, you wait for the mist to lift.

3. METAR EDDS 190620Z 05004KT 0800 R07/1100D FG OVC002 04/04 Q1030

Below special VFR. Fog with 800 m visibility and a 200 ft ceiling. The 1,100 m RVR is getting worse. You stay on the ground.

4. METAR LIMC 191350Z 20015G27KT 160V240 9999 FEW040CB SCT050 24/15 Q1009

The numbers clear the minima, but you do not go: there is a CB, gusts of 27 kt and a direction swinging through 80°. The legal minima say nothing about thunderstorms.

5. METAR LHBP 191430Z 31012KT CAVOK 18/02 Q1016 BECMG 33020G30KT

VFR possible now, but within two hours the wind rises to 20 kt gusting 30. Work out the crosswind with the gust before you go, and expect it to get worse.

6. TAF LROP 191100Z 1912/2018 24010KT 9999 SCT030 TEMPO 1914/1918 4000 SHRA BKN012 · arriving at 16:00 UTC

The arrival cannot be planned VFR. 16:00 falls in the TEMPO, with a 1,200 ft ceiling and 4 km. Delay, pick another aerodrome or leave earlier.

7. TAF LRSB 190500Z 1906/1915 VRB03KT 0400 FG VV001 BECMG 1908/1910 6000 NSC · departing at 09:00 UTC

Do not count on 09:00. The fog lifts in a BECMG between 08 and 10. For planning, treat the fog as there until 10:00 UTC, then check the METAR before you go.

8. TAF LEMD 191100Z 1912/2018 22010KT CAVOK PROB30 TEMPO 2004/2008 0500 FG · arriving at 06:00 UTC on the 20th

The main forecast is excellent, but there is a 30 % chance of fog with 500 m right at your time. A VFR pilot does not plan an arrival where almost a third of the outcomes are below minima: arrive later, or carry an alternate and the fuel to reach it.

9. METAR LEBL 191100Z 18010KT 9999 -RA FEW015 BKN030 OVC060 15/13 Q1011

VFR possible. The ceiling is BKN030, so 3,000 ft (FEW015 does not count). But 15/13 is only 2 °C between temperature and dew point, and in rain the cloud can lower. Keep an eye on the next METARs.

10. The METAR gives 25012KT and the ATIS says wind 244/12. Why the difference?

The METAR is relative to true north, the ATIS to magnetic north. With a variation of about 6° East: 250 − 6 = 244 magnetic. For the runway, use the ATIS or tower wind.

Got the wind from the METAR? Split it into components

On the navigation computer's Digital tab, pick "Wind components", enter the runway and the wind, and see the crosswind and headwind step by step.

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FlightDesk Aero articles are training material aligned with the EASA PPL syllabus. For real flights, use current official reports and forecasts, the AIP and your instructor's guidance. The decoder is a learning aid, not for operational use.