METAR Report Decoded

METAR – The type of report, METAR or SPECI precedes the body of all reports. 

KOKC – Station Identifier

011955Z – The date and time is coded in all reports as follows: the day of the month is the first two digits (01) followed by the hour (19), and the minutes (55). The coded time of observations is the actual time of the report or when the criteria for a SPECI is met or noted. If the report is a correction to a previously disseminated report, the time of the corrected report is the same time used in the report being corrected. The date and time group always ends with a Z indicating Zulu time (or UTC). For example, METAR KOKC 011955Z would be disseminated as the 2000 hour scheduled report for station KOKC taken on the 1st of the month at 1955 UTC. 

AUTO – The report modifier, AUTO, identifies the METAR/SPECI as a fully automated report with no human intervention or oversight. In the event of a corrected METAR or SPECI, the report modifier, COR, is substituted for AUTO. 

22015G25KT – Wind is the horizontal motion of air past a given point. It is measured in terms of velocity, which is a vector that includes direction and speed. It indicates the direction the wind is coming FROM.

In the wind group, the wind direction is coded as the first three digits (220) and is determined by averaging the recorded wind direction over a 2-minute period. It is coded in tens of degrees relative to true north using three figures. Directions less than 100 degrees are preceded with a
0. For example, a wind direction of 900 is coded as 090.


Immediately following the wind direction is the wind speed coded in two or three digits (15). Wind speed is determined by averaging the speed over a 2-minute period and is coded in whole knots using the units, tens digits and, when required, the hundreds digit. When wind speeds are less than 10 knots, a leading zero is used to maintain at least a two digit wind code. For
example, a wind speed of 8 knots will be coded 08KT. The wind group is always coded with a KT to indicate wind speeds are reported in knots. Other countries may use kilometers per hour (KPH) or meters per second (MPS) instead of knots.

Examples:
05008KT Wind 50 degrees at 8 knots
15014KT Wind 150 degrees at 14 knots
340112KT Wind 340 degrees at 112 knots 

Wind Gust. Wind speed data for the most recent 10 minutes is examined to evaluate the occurrence of gusts. Gusts are defined as rapid fluctuations in wind speed with a variation of 10 knots or more between peaks and lulls. The coded speed of the gust is the maximum instantaneous wind
speed. Wind gusts are coded in two or three digits immediately following the wind speed. Wind gusts are coded in whole knots using the units, tens, and, if required, the hundreds digit. For example, a wind out of the west at 20 knots with gusts to 35 knots would be coded 27020G35KT.

Variable Wind Direction (speed 6 knots or less). Wind direction may be considered variable when, during the previous 2-minute evaluation
period, the wind speed was 6 knots or less. In this case, the wind may be coded as VRB in place of the 3-digit wind direction. For example, if the wind speed was recorded as 3 knots, it would be coded VRB03KT.

180V250 – Variable Wind Direction (speed greater than 6 knots).  Wind direction may also be considered variable when, during the 2-minute evaluation period, it
varies by 60 degrees or more and the speed is greater than 6 knots. In this case a variable wind direction group immediately follows the wind group. The directional variability is coded in a clockwise direction and consists of the extremes of the wind directions separated by a V. For example, if the wind is variable from 180º to 240º at 10 knots, it would be coded 21010KT
180V240. 

Calm Wind. When no motion of air is detected, the wind is reported as calm. A calm wind is coded as 00000KT.

 

 3/4SM – Visibility is a measure of the opacity of the atmosphere.


Prevailing visibility is the reported visibility considered representative of recorded visibility conditions at the station during the time of observation. It is the greatest distance that can be seen throughout at least half of the horizon circle, not necessarily continuous.


Surface visibility is the prevailing visibility from the surface at manual stations or the visibility derived from sensors at automated stations.


The visibility group is coded as the surface visibility in statute miles. A space is coded between whole numbers and fractions of reportable visibility values. The visibility group ends with SM to indicate that the visibility is in statute miles. For example, a visibility of one and a half statute miles is coded 1 1/2SM. Other countries may use meters (no code).


Automated stations use an M to indicate “less than.” For example, M1/4SM means a visibility of less than one-quarter statute mile.

R17L/2600FT – Runway Visual Range (RVR) Group.

The runway visual range (RVR) is an instrument-derived value representing the horizontal distance a pilot may see down the runway.

RVR is reported whenever the station has RVR equipment and prevailing visibility is 1 statute mile or less and/or the RVR for the designated instrument runway is 6,000 feet or less. Otherwise the RVR group is omitted.

Runway visual range is coded in the following format: the initial R is code for runway and is followed by the runway number. When more than one runway is defined with the same runway number a directional letter is coded on the end of the runway number. Next is a solidus /;
followed by the visual range in feet and then FT completes the RVR report. For example, an RVR value for Runway 01L of 800 feet would be coded R01L/0800FT. Other countries may use meters.

RVR values are coded in increments of 100 feet up to 1,000 feet, increments of 200 feet from 1,000 feet to 3,000 feet, and increments of 500 feet from 3,000 feet to 6,000 feet. Manual RVR is not reported below 600 feet. At automated stations, RVR may be reported for up to four designated runways. 

When the RVR varies by more than one reportable value, the lowest and highest values will be shown with V between them indicating variable conditions. For example, the 10-minute RVR for runway 01L varying between 600 and 1,000 feet would be coded R01L/0600V1000FT.

If RVR is less than its lowest reportable value, the visual range group is preceded by M. For example, an RVR for runway 01L of less than 600 feet is coded R01L/M0600FT.

If RVR is greater than its highest reportable value, the visual range group is preceded by a P. For example, an RVR for runway 27 of greater than 6,000 feet will be coded R27/P6000FT.

+TSRA BR – Present Weather Group.  Heavy. TS = Thunderstorms.  RA = Rain. BR = MIST.


OVC010CB – Sky Condition Group.  Overcast at 1,000 feet with cumulonimbus. 

18/16 – Temperature/Dew Point Group

A2992 –  Altimeter

RMK AO2 TSB25 TS OHD MOV E SLP132 – Remarks (RMK). 

A02 – Type of Automated Station AO1 or AO2 are coded in all METAR/SPECI from automated stations. Automated stations without a precipitation discriminator are identified as AO1; automated stations with a
precipitation discriminator are identified as AO2. 

SLP132 – Sea-Level Pressure. At designated stations, the sea-level pressure is coded in the following format: the identifier SLP immediately followed by the sea level pressure in hectopascals. The hundreds and thousands units are not coded and must be inferred. For example, a sea-level pressure of
998.2 hectopascals is coded as SLP982. A sea-level pressure of 1013.2 hectopascals would be coded as SLP132. For a METAR, if sea-level pressure is not available, it is coded as SLPNO. 

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