16/04/2024
Posts

METAR – What is it? How to read?

METAR is an acronym for Meteorological Aerodrome Report or Meteorological Terminal Aviation Routine Weather Report.

METAR shows the short-term weather and meteorological information for an airport. It contains information such as temperature, dew point, wind direction and speed, cloud amount, visibility, pressure and more.

METAR data is extremely important for pilots to understand the weather in both the departure and arrival airports. Generally, metar information at an airport is updated and published every 30 minutes. For example metar publishment period can be in sequence like 1220Z – 1250Z – 1320Z …



Of course, how METAR data should be read is also critical. Because at first glance, it is can be difficult to understand what the many letters and numbers lined up in a row means.

Let’s all try to decipher a METAR message. Let our METAR massage be like:

LIMC 120840Z 13010G23KT 10SM SHRA SCT028 BKN080 17/11 Q1012 NOSIG

– LIMC is the ICAO code of the station where the metar report is broadcast.

– 120840Z, the first two digits of the expression is the day indicator. 12th day of the month.

– 0840Z expression is the time information in our metar report. İt is published in zulu time pointed with ‘Z’.

– The first three digits in the 13010G23KT, that is, 130 indicate the wind direction.

– 10G23KT statement also indicates that the wind blows at 10 knots gusting 23 knots. They indicate the winds speed.

– 10SM This refers to the visibility. The visibility in this example is 10 Statute Miles. In some metar reports it can be like 9999 and that means visibility is 10km or more. For example 4500 means visibility 4500 meters.

– SHRA stands for showers rain and refers to current meteorological events. There are many abbreviations in this group such as + TSRA like severe thunderstorm rain or PRFG partial Fog. See the table below for all of these expressions.

– SCT028 and BKN080 statements indicate Sky Conditions. The first three letters SCT and BKN are the codes for the amount of coverage in the sky. The next 028 and 080 represent the altitude value, ie Scattered cloudiness at 2800 feet altitude.

– 17/11 expression is the temperature and dew point values, respectively. So 17 is temperature information and 11 is dew point.

– Q1012 gives the altimeter pressure value. The local altimeter is 1012.

– NOSIC refund also means that no serious weather change is expected within the two-hour period after the metar is issued.

Below you will find the codes showing the cloudiness ratio.

METAR – codes

IntensityDescriptorPrecipitationObscuration
(-): LightMI: ShallowDZ: DrizzleBR: Mist
(): Moderate [No prefix]BC: PatchesRA: RainFG: Fog
(+): HeavyDR: Low DriftingSN: SnowFU: Smoke
 BL: BlowingSG: Snow GrainsVA: Volcanic Ash
 SH: ShowersIC: Ice CrystalsDU: Widespread Dust
 TS: ThunderstormPL: Ice PelletsSA: Sand
 FZ: FreezingGR: HailHZ: Haze
 PR: PartialGS: Small Hail &/or Snow PelletsPY: Spray
  UP: Unknown Precipitation 
Cloudiness Codes
NSC: No cloud
FEW: 1-2 off in 8
SCT:  Scattered – 3 – 4 off at 8
BKN: Broken – 5 – 7 off on 8
OVC: Overcast – 8 in 8 out