CertboundCan you decode a pasted report?
21 groups decoded or flagged.
| Group | Meaning |
|---|---|
METAR | Report type. Routine aviation weather observation. |
KOKC | Station. ICAO station identifier KOKC. |
011955Z | Time. Report time: day 01 at 19:55 UTC. The month and year are not encoded. |
AUTO | Status. Automated report without human intervention. |
22015G25KT | Wind. From 220 degrees true, 15 knots, gusting to 25 knots. |
180V250 | Wind variation. Wind direction varies between 180 and 250 degrees true. |
3/4SM | Visibility. 0.75 statute miles prevailing visibility. |
R17L/2600FT | Runway visual range. Runway 17L: 2600 feet. |
+TSRA | Weather. Heavy rain with thunderstorm. |
BR | Weather. mist. |
OVC010CB | Sky. Overcast (8 eighths): 1000 feet AGL, cumulonimbus; ceiling only if this is the lowest BKN, OVC or VV layer. |
18/16 | Temperature. Temperature 18 °C; dew point 16 °C. |
A2992 | Altimeter. Altimeter setting 29.92 inches of mercury. |
RMK | Remarks. Remarks follow; some groups need local or specialist interpretation. |
AO2 | Remarks. Automated station with a precipitation discriminator. |
TSB25 | Weather timing. thunderstorm began at minute 25 (hour not encoded). |
TS | Remarks weather. thunderstorm. |
OHD | Remarks. Overhead. |
MOV | Remarks. Moving. |
E | Remarks. East. |
SLP132 | Sea-level pressure. Sea-level pressure 1013.2 hPa. |
Paste one METAR or TAF below, then select Decode. The tool interprets common groups and leaves unsupported groups visible as Unrecognized. It does not certify that a report is complete, valid or safe to use. The example buttons load historical FAA teaching examples, not current weather.
The METAR comes from AC 00-45H with Change 2, section 3.1.5.1. The Pierre TAF comes from section 5.13.2.12.4. That circular is used here for its worked encoding examples, not as a current operational weather service. Pasted text stays in page memory and is cleared when you leave or refresh.
What comes first in a METAR?
Read the report type, station identifier and time. METAR KOKC 011955Z identifies a routine report at KOKC on day 01 at 19:55 UTC. Z is UTC, not local time. The month and year are not in this group. SPECI identifies a special observation; AUTO and COR describe automated and corrected reports.
The FAA circular, section 3.1.5, walks through the METAR body and remarks separately. Do not confuse the observation time with a TAF's issue time or forecast-validity period.
How do wind and visibility work?
22015G25KT means wind from 220 degrees true, at 15 knots, gusting to 25. 180V250 says its direction varies between 180 and 250 degrees. VRB03KT uses a variable direction, while 00000KT is calm.
3/4SM is three-quarters of a statute mile. 1 1/2SM is one and a half. P6SM is more than six, not exactly six. M1/4SM is less than one-quarter. An international report may give visibility in meters; 9999 means 10 kilometers or more. Runway visual range, such as R17L/2600FT, is a separate runway-specific measurement, not prevailing visibility.
Read the wind, visibility and runway-visual-range sections in AC 00-45H chapter 3. Units are part of the answer. Do not read meters as feet or statute miles as nautical miles.
What do weather and cloud groups mean?
Weather groups combine intensity, descriptors and phenomena. -RA is light rain, +TSRA is heavy rain with a thunderstorm, BR is mist and FZRA is freezing rain. VC puts the reported phenomenon in the vicinity rather than directly at the station.
Cloud heights are in hundreds of feet AGL. SCT025 means scattered clouds at 2,500 feet above ground. BKN010 is a broken layer at 1,000 feet AGL. The lowest broken, overcast or vertical-visibility layer defines the ceiling; scattered cloud by itself is not a ceiling. CB identifies cumulonimbus, and TCU towering cumulus. VV/// gives no usable vertical-visibility height.
CLR from an automated U.S. station means no cloud detected at or below 12,000 feet, not an unlimited clear sky. CAVOK has specific visibility, cloud and weather conditions; it is not just another spelling of clear. See AC 00-45H chapter 3 for the coding definitions.
How do you read temperature, pressure and remarks?
18/16 gives temperature and dew point in degrees Celsius. An M means minus: M05/M10 is −5 °C and −10 °C. A2992 is an altimeter setting of 29.92 inches of mercury. Q1013 uses hectopascals instead.
RMK starts the remarks. AO2 describes an automated station with a precipitation discriminator. SLP132 is sea-level pressure of 1013.2 hPa, not an altimeter setting of 13.2. A precise-temperature group such as T00261015 gives 2.6 °C and a dew point of −1.5 °C. The decoder covers these basics, precipitation totals and simple weather start or end times; specialized remarks may remain unrecognized.
The remarks definitions are in AC 00-45H section 3.1.6. Always keep an unsupported group in view rather than treating it as no weather.
How does a TAF show changes?
A TAF includes an issue time and a validity range. 1112/1212 is valid from day 11 at 12:00 UTC to day 12 at 12:00 UTC. It may cross midnight or a month boundary.
| Group | Meaning | How to read later values |
|---|---|---|
| FM111500 | From day 11 at 15:00 UTC | A new prevailing forecast replaces the preceding one |
| TEMPO 1112/1114 | Temporary fluctuations during that period | Changed elements are temporary; unchanged elements remain as previously forecast |
| BECMG 1114/1116 | A transition during that period | The new conditions prevail after the transition; used in some military and international TAFs |
| PROB30 1200/1204 | A 30% probability during that period | A chance of the stated conditions, not a 30% reduction in visibility |
The FAA circular's TAF section, 5.13, explains FM, TEMPO and probability groups. NWS TAFs use PROB30, while military and international TAFs may also use PROB40. The FAA AIM weather section, 7-1-28 and 7-1-30, explains BECMG and notes that NWS does not use it. TEMPO fluctuations last one hour or less each and cover less than half the stated period in total. WS020/35035KT is low-level wind shear at 2,000 feet AGL, with wind there from 350 degrees true at 35 knots.
How can you use this for Part 107 study?
Decode a short report by hand first. Compare your units and time periods with the result, then explain what each group says without using the abbreviations. The tool does not judge whether an operation complies with weather minimums.
Use the study guide for weather concepts and the 46-question FAA sample set for weather questions with Certbound's explanations and citations. The sectional legend guide covers a different set of symbols and altitude references. FAA sources checked October 17, 2026.