Free METAR and TAF Decoder
Paste a METAR, SPECI or TAF to read the wind, visibility, weather, cloud and forecast changes in plain language.
What is a METAR and TAF Decoder?
METARs are hourly weather observations from airports, and TAFs are their forecasts for the next day or so. Both are written in a compact code, such as 18012G20KT for wind. This decoder turns every group into plain language.
It reads METAR, SPECI and TAF in both the international metric style and the US style with statute miles and inHg. Wind, visibility, runway visual range, present and recent weather, cloud layers, temperatures, pressure, trends and TAF change periods are decoded, along with common US remarks and the flight category.
Key Features
Every Group Decoded
Wind, gusts, visibility, runway visual range, weather, cloud, temperature, dew point and pressure.
TAF Change Periods
FM, BECMG, TEMPO and PROB groups become labelled sections with their times.
Flight Category
VFR, MVFR, IFR or LIFR from the ceiling and visibility of each METAR.
Group by Group
A second view pairs each raw group with its meaning, the fastest way to learn the code.
Both Unit Systems
Knots with km/h, statute miles with kilometres, and inHg with hPa side by side.
Perfect for everyone
- Student and private pilots
- Flight dispatchers
- Drone operators
- Sailors and weather enthusiasts
How to Use the METAR and TAF Decoder
Paste one report or many and choose a view.
Get the Report
Copy a METAR or TAF from aviationweather.gov, your flight planning app or a briefing.
Paste It
Several reports at once are fine. Each one starts with its station and time.
Read It Plainly
Plain language lists each field, with TAF change periods as their own sections.
Learn the Code
Group by group shows what each raw group means, in the order it was written.
Reports, Decoded
Each row is a METAR or TAF as it’s published, and each answer is this decoder’s output in the mode on the chip. Read the code yourself first, then reveal the answer.
“METAR KJFK 271651Z 18012G20KT 10SM FEW050 BKN250 22/14 A2992 RMK AO2 SLP132 T02220144”
“METAR EGLL 271650Z 23015G27KT 200V270 4000 -SHRA BR BKN008 OVC015 12/11 Q1004 TEMPO 3000 SHRA”
“METAR KSFO 271656Z 28010KT 1/4SM FG VV001 13/13 A2995”
“METAR EGLL 271650Z 23015KT 0800 R27L/0550V0800U +TSRAGR FG VV002 12/11 Q1004”
“METAR LFPG 271700Z 00000KT CAVOK 18/09 Q1021 NOSIG”
“TAF EGLL 271658Z 2718/2824 24012KT 9999 SCT030 TEMPO 2718/2722 -SHRA BKN014 PROB30 TEMPO 2800/2806 7000 BR BECMG 2810/2813 31015G25KT FM281800 30010KT CAVOK”
“TAF KORD 271730Z 2718/2824 22015G25KT P6SM SCT050 FM272200 24010KT P6SM BKN040 FM280600 30012KT 4SM -SHRA OVC012”
“METAR CYYZ 271700Z 03018G28KT 1 1/2SM -FZRA -SN BR OVC006 M02/M03 A2968”
“KBOS 271654Z 05008KT 2SM BR OVC006 12/11 A3001 KLGA 271651Z VRB03KT 10SM SKC 21/12 A2993”
“METAR 271651Z 18012KT 10SM”
The Groups in a METAR
A METAR is a fixed sequence of groups. These ten appear in almost every report, in this order.
Station
A four-letter ICAO code: K for the contiguous US, EG for the UK, LF for France.
“Which airport is EGLL?”
Time
Day of the month and time in UTC, ending in Z.
“What does 271651Z mean?”
Wind
Direction in degrees true, speed, optional gust after G, then the unit.
“What does 18012G20KT mean?”
Visibility
Metres in four digits (9999 means 10 km or more) or statute miles ending SM.
“How far is 10SM?”
Runway Visual Range
R, the runway, then the distance a pilot can see along it, with a trend letter.
“What does U mean at the end?”
Weather
An intensity, a descriptor and one or more phenomena, such as -SHRA.
“What is -SHRA?”
Clouds
Cover in eighths (FEW, SCT, BKN, OVC) and the base in hundreds of feet.
“How high is BKN014?”
Temperature
Temperature and dew point in °C, with M for minus.
“What is M02/M03?”
Pressure
A and inches of mercury in the US, Q and hectopascals elsewhere.
“What is A2992 in hPa?”
Remarks
Everything after RMK, mostly US station details such as AO2 and SLP.
“What does SLP132 mean?”
How a TAF Changes Over Time
A TAF starts with the conditions expected at the start of its validity period, then lists changes. Each change group says when and how firmly the forecast changes.
Validity Period
2718/2824 means from day 27 at 18:00 to day 28 at 24:00 UTC. Big airports get 24 or 30 hours.
FM
From a set time, such as FM281800, the conditions that follow replace everything before.
BECMG
A gradual change over the period given, after which the new conditions hold.
TEMPO
Temporary fluctuations lasting under an hour each, covering less than half the period.
PROB30 and PROB40
A 30 or 40 percent chance of the conditions, sometimes combined with TEMPO.
TX and TN
Forecast highest and lowest temperatures and when they’re expected, common in Europe.
Flight Categories
US pilots sum up a METAR’s ceiling and visibility in one of four categories. The ceiling is the lowest broken or overcast layer, and the worse of the two measures sets the category.
VFR
Ceiling above 3,000 ft and visibility above 5 statute miles. Fine for visual flying.
MVFR
Ceiling 1,000 to 3,000 ft or visibility 3 to 5 miles. Legal for VFR, but take care.
IFR
Ceiling 500 to under 1,000 ft or visibility 1 to under 3 miles. Instrument rules apply.
LIFR
Ceiling under 500 ft or visibility under 1 mile, the conditions that close smaller airports.
When to Decode METARs and TAFs
Whenever you need the weather at an airport without squinting at the code.
Pre-Flight Planning
Check departure, destination and alternate weather while learning to read the raw code.
Student Pilot Study
Practise with the group-by-group view before written exams and checkrides.
Drone Operations
Check wind, gusts, visibility and ceiling before a flight near an airport.
Travel Delays
See whether fog, thunderstorms or low cloud at an airport explain a delay.
Building Weather Apps
Compare your parser’s output with this decoder’s, group by group.
Reading Pitfalls
Easy mistakes when reading the code by eye.
UTC, Not Local
Every time is UTC. Convert before comparing with your departure time.
Hundreds of Feet
Cloud heights are in hundreds of feet above the airport, so BKN008 is 800 ft, not 8,000.
Magnetic Versus True
METAR winds are true. Runways and ATIS winds are magnetic, which can differ by 10° or more.
9999 Isn’t 9.9 km
It means 10 km or more, the most the code can say.
TEMPO Isn’t the Main Forecast
TEMPO conditions come and go. Plan for them, but expect the base forecast most of the time.
Old Reports
A METAR is an hourly snapshot. Check the time group before trusting it.