How to read a METAR without getting it wrong: group by group

A METAR looks like a random string of characters the first time you see one. It's actually the opposite: the groups always come in the same order, and knowing which one you're looking at is all it takes to decode it. Once the structure clicks, a METAR reads in fifteen seconds.

Take a full example and take it apart:

KJFK 181351Z 24012G25KT 200V280 10SM -RA BR SCT008 BKN015 12/11 A2983 TEMPO 3SM RADZ BKN006

The skeleton: 8 groups in a fixed order

Group	Example	What it says
Station	`KJFK`	ICAO code of the airfield
Date/time	`181351Z`	The 18th at 13:51 UTC
Wind	`24012G25KT`	From 240°, 12 kt, gusting 25 kt
Visibility	`10SM`	10 statute miles
Present weather	`-RA BR`	Light rain, mist
Clouds	`SCT008 BKN015`	See below
Temperatures	`12/11`	12 °C, dew point 11 °C
Pressure	`A2983`	Altimeter setting 29.83 inHg

Anything after that block is a trend or remark: TEMPO, BECMG, NOSIG, RMK.

An AUTO tag (not present here) would mean a fully automated observation, with no human observer — such a station sees thunderstorms and cloud types poorly, and only looks straight up from the sensor.

Wind: direction is in true degrees

24012G25KT breaks into three parts: 240 = direction the wind is coming from, 12 = speed in knots, G25 = gusting to 25 kt.

Two classic traps:

METAR wind direction is given relative to true north, while the tower gives you wind relative to magnetic north over the radio. The difference (variation) can be significant depending on where you are, and it's a favorite exam question.
200V280 means the direction has varied between 200° and 280° — that's an unstable wind, not a harmless range when you're planning a crosswind landing.

VRB03KT means variable at 3 kt (typically light wind with no established direction), and 00000KT means calm.

Visibility and present weather: the part that decides

In the US, visibility is reported in statute miles (10SM), elsewhere in meters up to 9999 m. 9999 means 10 km or more — a coding ceiling, not literally 9,999 m of visibility. 0000 means less than 50 m.

Present weather combines an intensity and a phenomenon:

Intensity: - light, nothing = moderate, + heavy.
Common phenomena: RA rain, DZ drizzle, SN snow, SHRA rain showers, TS thunderstorm, BR mist (visibility roughly 5/8 to 3 miles / 1,000–5,000 m), FG fog (below roughly 5/8 mile / 1,000 m).

Remember: BR and FG are not two words for the same thing. The visibility threshold between them separates an uncomfortable VFR flight from an impossible one.

Clouds: coverage in eighths, base in hundreds of feet

SCT008 BKN015 reads: scattered clouds at 800 ft, broken ceiling at 1,500 ft.

Code	Coverage	Meaning
`FEW`	1–2 oktas	A few clouds
`SCT`	3–4 oktas	Scattered
`BKN`	5–7 oktas	Broken
`OVC`	8 oktas	Overcast

Two rules that cost points on the exam:

Height is given in hundreds of feet above the ground (AGL), not above sea level. BKN015 = 1,500 ft above the runway.
The ceiling is the base of the first BKN or OVC layer. Here, the ceiling is 1,500 ft — not 800 ft, despite the SCT layer underneath.

CAVOK replaces visibility, weather, and clouds all at once: visibility 10 km or more, no cloud below 5,000 ft (or below the minimum sector altitude if higher), no cumulonimbus, no significant phenomena. NSC means no significant cloud, NCD means no cloud detected by an automated sensor.

Temperature, dew point, altimeter setting: three numbers, three decisions

12/11: 12 °C with an 11 °C dew point. The spread between the two is the useful information. A 1 °C spread, with temperature dropping later in the day, means fog is forming. A 10 °C spread means dry air.

Negative values are prefixed with M: M02/M04 = −2 °C, dew point −4 °C.

A2983 is the altimeter setting in inches of mercury — the same reference you dial in to read altitude, reported as QNH in hectopascals outside the US (Q1009, for example).

For carburetor icing risk, the temperature/dew point spread matters more than temperature alone: mild, humid air ices a carburetor far more readily than cold, dry air.

Trends: TEMPO, BECMG, NOSIG

In our example, TEMPO 3SM RADZ BKN006 announces temporary periods (each under an hour, less than half the total period) with 3 statute miles visibility, rain and drizzle, ceiling at 600 ft.

TEMPO: temporary fluctuations, the condition reverts to the described state afterward.
BECMG: a lasting change toward a new state.
NOSIG: no significant change expected within the next 2 hours.

This is the part students skip most often — and the one that turns a planned flight into a turnback.

The full read, in one sentence

Our METAR becomes: at JFK on the 18th at 13:51 UTC, wind from 240° at 12 kt gusting 25 kt with direction varying between 200° and 280°, visibility 10 miles under light rain and mist, scattered clouds at 800 ft and a broken ceiling at 1,500 ft, 12 °C with an 11 °C dew point, altimeter 29.83, with temporary periods down to 3 miles visibility and a 600 ft ceiling.

Translated into a decision: gusty crosswind, low ceiling, a 1 °C temperature/dew point spread, and temporary drops below VFR minimums. Not a METAR to debate for long.

What this changes in flight

A METAR isn't read to be decoded — it's read to decide. Three habits cover most of it:

Ceiling and visibility against your personal minimums and your airspace's minimums.
The temperature/dew point spread, especially late in the day and in cold season.
The trend group, because it describes the field at your arrival time, not at the time you're reading the report.

Everything else is context. And if one group stops you, remember that its position in the sequence is usually enough to guess what it describes.

Disclaimer: this article is a study aid. It does not replace official documentation in force (AIP, EASA regulations, aircraft flight manual) or your instructor's guidance. In case of discrepancy, the official source prevails.