METAR Quiz: Decode and Read Aviation Weather Reports

Q: What’s the operational difference between METAR and SPECI?

METAR is the routine surface observation issued on a scheduled cycle, while SPECI is an unscheduled special report issued when certain significant weather changes occur. In practice, SPECI often captures rapid deterioration or improvement (visibility, ceiling, wind, precip) that can change approach legality or alternates faster than the routine cycle.

Q: When does a cloud layer become a “ceiling” in a METAR?

A ceiling is the lowest layer reported as BKN or OVC , or a VV (vertical visibility) value. FEW and SCT layers are not ceilings, even if they’re low. Example: SCT005 BKN020 has a 2,000 ft AGL ceiling.

Q: How should I interpret “9999” visibility in an international METAR?

In many ICAO-format METARs, visibility is reported in meters . 9999 means 10 km or more , not “9,999 meters exactly” and not statute miles. Treat it as “good visibility,” then move to present weather and ceiling to determine VFR/IFR implications.

Q: Does METAR wind direction use TRUE or MAGNETIC degrees?

METAR wind direction is reported in degrees true . Runway numbers are based on magnetic heading, so any comparison requires you to be mindful of local variation and operational context. The quiz commonly targets errors where pilots “force” METAR wind to match runway magnetic without thinking.

Q: Which U.S. “RMK” items are worth decoding first?

Prioritize remarks that change risk decisions: PK WND (peak wind), WSHFT (wind shift), SLP### (sea-level pressure), and the precise T group (temperature/dew point in tenths °C) when you’re assessing marginal icing/fog potential. Many other RMK items are informational, but these are common checkride and real-world traps.

8 – 55 Questions 15 min

Decode METAR groups exactly as defined in ICAO Annex 3 and the FAA Aeronautical Information Manual, including wind variability, RVR, ceiling, and remarks that change IFR/VFR decisions. Accurate interpretation supports 14 CFR §91.103 preflight action; misreading visibility or altimeter can lead to unstable approaches, checkride failures, and FAA certificate suspension or revocation after an incident.

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1In a standard METAR, which group immediately follows the station identifier (e.g., KDEN)?

2Scattered clouds (SCT) define a ceiling for approach minima.

True / False

3What does the wind group “00000KT” mean in a METAR?

4A2992 in a U.S. METAR reports:

5“P6SM” means the prevailing visibility is exactly 6 statute miles.

True / False

6In “23012G22KT,” the “12” is the sustained wind speed and “22” is the gust speed.

True / False

7Q1013 indicates an altimeter setting of 1013 inches of mercury.

True / False

8What does the METAR modifier “COR” indicate?

9Arrange these present weather components in the order they appear within a single weather group.

Put in order

1Descriptor (e.g., SH, TS, FZ)

2Intensity (e.g., - or +)

3Phenomenon (e.g., RA, SN, FG)

4Phenomenon (second code, if included)

10In an ICAO-format METAR, the prevailing visibility group “9999” indicates:

11Select all that apply. Which statements about METAR wind encoding are correct?

Select all that apply

12Arrange these METAR groups in the order they typically appear (left to right) after the time group.

Put in order

1Sky condition

2Altimeter

3Visibility

4Wind

5Modifier (AUTO/COR)

13The DDHHMMZ time group in a METAR is reported in UTC (Zulu).

True / False

14Given “SCT020 BKN040,” what ceiling should you use for planning?

15How should you interpret “R06/1200V1800FT” in a METAR?

16Arrange the components of a present weather group in the order you decode them (left to right).

Put in order

1Intensity symbol (+/−/none)

2Phenomena (e.g., RA, SN, FG)

3Second phenomenon (if present)

4Descriptor (e.g., SH, TS, FZ)

17Select all that apply. Which sky condition codes can establish an official ceiling in a METAR?

Select all that apply

18Select all that apply. In “R23/0600U,” what can you conclude?

Select all that apply

19Arrange the steps to make a quick crosswind and gust planning assessment from a METAR wind group.

Put in order

1Compare to aircraft/personal limits

2Find the runway heading in use

3Add gust factor for control margin

4Compute the wind-runway angle

5Use sustained wind for baseline crosswind component

20A night departure METAR shows “00000KT 1/2SM FG VV002.” What ceiling should be treated as controlling?

21What does “-SHRA” mean?

22You see “4500” as the visibility group in an international METAR with no “SM” shown. What does it most likely represent?

23Select all that apply. For 14 CFR §91.103 preflight planning on an IFR flight, which METAR elements are typically most critical to decode correctly before committing to an approach plan?

Select all that apply

24An international METAR includes “Q1009.” Approximately what is this in inches of mercury (inHg)?

25Select all that apply. Which statements about the “A####” and “Q####” pressure groups are correct?

Select all that apply

26Select all that apply. You see “27015G25KT” and runway 22 is in use. Which immediate planning actions are appropriate?

Select all that apply

27Select all that apply. Which items are commonly found in the U.S. “RMK” section rather than the main body of the METAR?

Select all that apply

28A METAR includes the group “M02/M06.” What are the temperature and dew point?

29What does the appended group “180V240” indicate when it follows a wind group?

Disclaimer

This quiz is for educational and training purposes only. It does not constitute professional certification or legal compliance verification.

METAR decoding pitfalls that drive wrong go/no-go decisions

Most METAR errors come from reading a familiar group with the wrong rule set (U.S. vs ICAO), or from treating “format” as trivia instead of an operational control input. These are the misses that most often flip a legal/safer plan into an unacceptable one.

Wind groups: VRB, variability ranges, gusts

Confusing VRB with a directional range: VRB03KT means direction is variable with 3 kt wind; 180V240 is an appended range showing direction varying between 180° and 240°.
Assuming wind direction is magnetic: METAR wind direction is reported in degrees true. Don’t mentally “correct” it to match runway magnetic headings.
Over-reading gusts: In 23012G22KT, 12 is sustained; G22 is peak gust, not an average and not a separate “second wind.”

Visibility and RVR: units and qualifiers

Forgetting the unit system: U.S. METAR visibility is typically statute miles (SM); many international METARs use meters (e.g., 9999 = 10 km or more).
Ignoring RVR variability/trend: R06/1200V1800FT varies; R23/0600U includes a tendency (U up, D down, N no change).
Misreading “P” and “M” modifiers: P6SM is “greater than 6 SM”; in RVR, P can indicate “greater than” and M can indicate “less than.”

Ceiling and cloud heights: what legally counts

Calling SCT or FEW a ceiling: Only BKN, OVC, or VV establish a ceiling. Example: SCT020 BKN040 → ceiling 4,000 ft AGL.
Mixing AGL with MSL: METAR cloud heights are in hundreds of feet AGL (BKN040 = 4,000 ft AGL), not MSL.

Temperature/altimeter: sign and units

Missing the “M” for minus: M02/M06 changes icing probability, braking action expectations, and engine/airframe limitations.
Mixing altimeter systems: A2992 is inches of mercury; Q1013 is hPa. Don’t combine A- and Q-logic in the same brief.

METAR TAC decoding quick reference (ICAO Annex 3 + FAA AIM essentials)

Printable note: Use your browser’s print function to print this sheet or save it as a PDF for offline study and quick preflight review.

Canonical METAR order (left to right)

Type: METAR (routine) or SPECI (special)
Station: ICAO identifier (e.g., KJFK, EGLL)
Time: DDHHMMZ (UTC/Zulu)
Modifier: AUTO (automated) / COR (corrected)
Wind: dddff(f)GggKT, VRBffKT, or 00000KT (calm); optional dddVddd variability
Visibility: U.S. often in SM (fractions allowed); many international METARs use meters (9999 = ≥10 km)
RVR (if reported): Rrr/####FT, optional V#### and U/D/N tendency
Present weather: intensity + descriptor + phenomenon (e.g., -SHRA, +TSRA, FZFG)
Sky condition: FEW/SCT/BKN/OVC/VV + height (hundreds of ft AGL) + CB/TCU when applicable
Temp/dew point: TT/DD in °C; M = minus
Altimeter/QNH: A#### (inHg) or Q#### (hPa)
Remarks: RMK (U.S. detail-heavy section)

Decision-critical rules that show up in quiz questions

Ceiling rule: ceiling = lowest BKN, OVC, or VV. FEW/SCT do not count as a ceiling.
Wind direction is TRUE: compare to runway heading with care; crosswind planning belongs in your aircraft/airport context.
VRB vs range: VRB commonly appears with light winds; a dddVddd range is appended when criteria for variability reporting are met.
RVR parsing: R06/1200FT = runway 06 RVR 1200 ft; R06/1200V1800FT = variable; R06/1200U = improving trend.
Negative temps: M00 is still at/below freezing; don’t miss the sign when assessing icing/frost risk.

U.S. remarks (RMK) quick reads

AO1/AO2: automated station without/with a precipitation discriminator
SLP###: sea-level pressure in hPa (e.g., SLP132 ≈ 1013.2 hPa)
T0snT1sn: precise temperature/dew point in tenths °C (e.g., T00261004)
PK WND dddff/HHMM: peak wind and time
P####: precipitation in hundredths of an inch (U.S. convention)

Operational METAR scenario drills for VFR/IFR planning and approach legality

Use these prompts like a preflight brief: decode the exact groups, then state the operational meaning (ceiling, prevailing visibility, runway-specific limitations, and trend). The goal is to build a repeatable left-to-right workflow that matches ICAO/FAA coding.

Wind variability trap: METAR KXXX 071855Z 23012G22KT 180V240 3SM -SHRA SCT020 BKN040 18/16 A2992

Identify sustained wind, gust, and what the 180V240 range means. What is the ceiling, and which group legally establishes it?
Calm vs “from 000”: METAR KXXX 071856Z 00000KT 1/2SM R18/1600FT FG VV002 00/00 A3010

State whether winds are calm or northerly. Determine the controlling visibility value for an approach brief, and whether VV002 creates a ceiling.
RVR variability and tendency: METAR KXXX 071900Z 12008KT 1/4SM R06/0800V1400FT U SN OVC004 M01/M03 A2988

Translate the RVR in plain language, including the variability and trend. What’s the ceiling, and how does the temperature/dew point pair affect icing concern?
International visibility units: METAR EGXX 071920Z 21015KT 9999 -RA BKN012 12/10 Q1016

Explain what 9999 means (and what it does not mean). Convert the ceiling into feet AGL, and state the pressure unit implied by Q1016.
“No ceiling” misconception: METAR KXXX 071945Z 31006KT 6SM HZ SCT008 SCT020 25/22 A2996 RMK AO2

Is there a ceiling? If not, what should you report as the “lowest cloud layer” versus “ceiling” in a briefing? What does AO2 tell you about the observing system?
Altimeter/QNH mix-up: METAR KXXX 072000Z 09010KT 10SM FEW050 05/M02 A3005

Extract the altimeter setting in inHg and interpret the negative dew point. Describe one concrete way a wrong unit assumption (A vs Q) could corrupt performance/altitude planning.

Authoritative METAR standards and FAA/NOAA references

FAA Aeronautical Information Manual (AIM), Chapter 7 — FAA guidance for aviation weather products, including METAR code usage and decoding context for U.S. operations.
FAA Order JO 7900.5D, Surface Weather Observing — Detailed FAA standards for METAR/SPECI elements, observing responsibilities, and reporting conventions used by U.S. weather reporting stations.
NOAA Aviation Weather Center (AWC) Help — Official NOAA/NCEP help for using AWC products and understanding how METAR/TAF data are presented and accessed.
NOAA AWC Data API Documentation — Technical reference for retrieving official METAR data programmatically, useful for practice workflows and validation against raw reports.
14 CFR §91.103 (Preflight action) — Regulatory text requiring pilots in command to become familiar with relevant weather and flight information before flight.

METAR decoding FAQ for pilots, dispatchers, and checkride prep

What’s the operational difference between METAR and SPECI?

METAR is the routine surface observation issued on a scheduled cycle, while SPECI is an unscheduled special report issued when certain significant weather changes occur. In practice, SPECI often captures rapid deterioration or improvement (visibility, ceiling, wind, precip) that can change approach legality or alternates faster than the routine cycle.

When does a cloud layer become a “ceiling” in a METAR?

A ceiling is the lowest layer reported as BKN or OVC, or a VV (vertical visibility) value. FEW and SCT layers are not ceilings, even if they’re low. Example: SCT005 BKN020 has a 2,000 ft AGL ceiling.

How should I interpret “9999” visibility in an international METAR?

In many ICAO-format METARs, visibility is reported in meters. 9999 means 10 km or more, not “9,999 meters exactly” and not statute miles. Treat it as “good visibility,” then move to present weather and ceiling to determine VFR/IFR implications.

Does METAR wind direction use TRUE or MAGNETIC degrees?

METAR wind direction is reported in degrees true. Runway numbers are based on magnetic heading, so any comparison requires you to be mindful of local variation and operational context. The quiz commonly targets errors where pilots “force” METAR wind to match runway magnetic without thinking.

What do the RVR trend letters (U/D/N) actually tell me?

In an RVR group, U indicates the RVR is trending upward (improving), D downward (deteriorating), and N no distinct change. This trend matters when visibility is near minima: a legal value that is falling can be operationally riskier than the same value improving.

Which U.S. “RMK” items are worth decoding first?

Prioritize remarks that change risk decisions: PK WND (peak wind), WSHFT (wind shift), SLP### (sea-level pressure), and the precise T group (temperature/dew point in tenths °C) when you’re assessing marginal icing/fog potential. Many other RMK items are informational, but these are common checkride and real-world traps.

METAR decoding: 5 decision-grade takeaways (not memorization tricks)

Decode left-to-right in the published order so you don’t let remarks or a familiar cloud code distract you from the controlling visibility, ceiling, and wind.
Separate “cloud layers” from “ceiling” every time: only BKN/OVC/VV create a ceiling; FEW/SCT are never ceilings, even if they’re low.
Always confirm units before interpreting magnitude: SM vs meters for visibility, A#### vs Q#### for pressure, and feet for RVR.
Treat RVR as runway-specific and trend-aware: variability (V####) and tendency (U/D/N) can change whether conditions are stable enough to commit to an approach.
Don’t drop the minus sign: the “M” in temperature/dew point is operationally meaningful for icing, braking action expectations, and marginal fog/frost setups.

METAR glossary with in-report examples (quiz-aligned definitions)

METAR: Routine aerodrome surface weather report in standardized code. Example: METAR KDEN 071853Z ...
SPECI: Special (unscheduled) observation issued for significant changes. Example: SPECI KDEN 071910Z ...
DDHHMMZ: Observation time group: day of month, hour, minute in UTC (“Z”). Example: 071855Z = the 7th at 18:55 UTC.
VRB: Variable wind direction indicator used with light winds. Example: VRB03KT = variable direction at 3 kt.
dddVddd: Directional variability range appended to the wind group. Example: 180V240 = wind varying between 180° and 240°.
RVR (Runway Visual Range): Runway-specific measured visibility distance, typically in feet in U.S. METARs. Example: R06/1200V1800FT = runway 06 RVR variable 1200–1800 ft.
Ceiling: The lowest BKN, OVC, or VV layer. Example: SCT020 BKN040 → ceiling 4,000 ft AGL.
VV###: Vertical visibility (obscured sky), reported in hundreds of feet AGL. Example: VV002 = vertical visibility 200 ft.
9999: In many ICAO-format METARs, prevailing visibility of 10 km or more. Example: 9999 -RA BKN012.
A#### / Q####: Altimeter setting formats: A2992 = 29.92 inHg; Q1013 = 1013 hPa. Example: ... A3005 or ... Q1016.
RMK: Start of remarks section (U.S. detail often lives here). Example: RMK AO2 SLP132.