Guides / Weather
Weather · 8 min read

How to read a METAR

A METAR looks like line noise until you know it's just the same eight things in the same order, every time. Here's the order, and what each group is actually telling you.

A METAR is an observation — what the weather is at an airport, usually issued once an hour near the top of the hour. It is not a forecast; that's the TAF. Special observations (SPECI) are issued in between when something changes significantly.

KSUS 062253Z 28014G22KT 10SM FEW045 SCT120 24/13 A3001 RMK AO2

Read left to right. Every group is optional except the station, time and wind — if the weather is quiet, groups simply don't appear.

1. Station and time

KSUS is the ICAO identifier. 062253Z is the 6th of the month at 2253 Zulu — UTC, always, never local. That Z is the single most common source of student confusion, and it matters: a report timestamped 0253Z in the US is yesterday evening, not this morning.

You may also see AUTO (fully automated station, no human augmentation) or COR (a correction to a previous report).

2. Wind

28014G22KT is wind from 280° true at 14 knots, gusting 22.

Two traps worth internalising early:

Variants: VRB05KT is variable direction at 5 knots. 00000KT is calm. 28014KT 250V310 means the direction has been varying between 250 and 310.

3. Visibility

10SM is 10 statute miles — in the US, prevailing visibility in statute miles. 10SM is the maximum an automated station reports, so it really means "10 or more."

Fractions appear as you'd write them: 1 1/2SM, 1/2SM. Below a quarter mile you'll see M1/4SM, where M means "less than", not "minus".

4. Present weather

Absent in our example, because nothing was happening. When present it's built from an intensity, a descriptor and a phenomenon:

So -SHRA is light rain showers, +TSRA is a thunderstorm with heavy rain, and FZRA is freezing rain — which for a light aircraft is a hard stop, not a factor to weigh.

5. Sky condition

FEW045 SCT120 is few at 4,500 and scattered at 12,000. Heights are in hundreds of feet above ground level, so add two zeros and remember it's AGL, not MSL.

The coverage codes describe how much of the sky is covered, in eighths:

The ceiling is the lowest broken or overcast layer — or the vertical visibility. Few and scattered layers are not ceilings, however low they are. This trips up more students than any other item on this page, and it's the number your personal minimums are actually written against.

6. Temperature and dewpoint

24/13 is 24°C with a 13°C dewpoint, always in Celsius. M means minus: M04/M09 is −4°C and −9°C.

The spread is what you care about. A tight spread means the air is close to saturation — fog or low stratus is plausible, especially as things cool near sunrise. A spread of 11°C, as above, is comfortably dry. As a rough rule, watch closely once the spread is under about 4°C and falling.

Temperature also drives density altitude, which drives whether the runway is long enough. On a hot day at elevation, that's the number that hurts you.

7. Altimeter

A3001 is 30.01 inches of mercury. Set it, and reset it as you cross into a new reporting area — flying from high to low pressure without updating leaves your altimeter reading higher than you actually are.

8. Remarks

Everything after RMK. Some is housekeeping (AO2 means an automated station that can distinguish rain from snow), but genuinely useful items hide here:

Flight categories

Ceiling and visibility together determine the category. It's the ceiling or the visibility — whichever is worse decides:

CategoryCeilingVisibility
VFRGreater than 3,000 ft AGLGreater than 5 SM
MVFR1,000 to 3,000 ft AGL3 to 5 SM
IFR500 to below 1,000 ft AGL1 to below 3 SM
LIFRBelow 500 ft AGLBelow 1 SM

Our example — no ceiling below 12,000 and 10 SM — is comfortably VFR.

Worth saying plainly: these categories describe the weather, not whether you should go. A legal VFR day with a 25-knot direct crosswind and a 12-hour duty day behind you is a bad idea that no category will flag. That's the job of personal minimums.

Put it together

KDEN 070153Z 36018G28KT 1 1/2SM -SN BKN008 OVC015 M03/M05 A2989 RMK AO2 PK WND 36032/0145

Denver, 7th at 0153Z. Wind from 360° at 18 gusting 28, peaking at 32 earlier. Visibility 1½ miles in light snow. Broken at 800, overcast at 1,500 — the ceiling is 800 ft, the broken layer. Temperature −3°C, dewpoint −5°C, a 2° spread. Altimeter 29.89.

Ceiling 800 and visibility 1½ puts this squarely in IFR. For a VFR pilot that's the end of the conversation, and the gusts and snow mean it isn't close.

Practice beats memorisation. Decoding is a skill that only sticks with reps. SkyBrief gives you a real METAR to decode every day, and shows the plain-English version alongside the raw text so you can check yourself — free, no subscription.
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This guide is educational and simplified in places. The authoritative references are the Aviation Weather Handbook (FAA-H-8083-28) and AIM Chapter 7. Always obtain an official weather briefing before flight.

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