1.1 METAR Reports

METAR stands for Meteorological Aerodrome Report.

These are standardized aviation weather summaries issued hourly, providing essential information such as wind, visibility, weather phenomena, sky condition, temperature, and pressure at airports.

Quick Weather Overview
Critical Aviation Info
Standardized Format
Timely Updates

Key Notes:

Quick Weather Overview: METARs provide a concise overview of current weather conditions at a specific location.

Critical Aviation Info: Pilots rely on METARs to make decisions about takeoffs, landings, and in-flight operations.

Standardized Format: Follow an internationally recognized format, ensuring consistency and ease of interpretation.

Timely Updates: Issued regularly, METARs offer real-time information, allowing for up-to-date weather assessments for aviation.

Study Guide

Intro to METAR Reports

Meteorological Aerodrome Report (METAR)

Accurate depiction of the current weather conditions.

Issued Frequency

Typically issued once an hour, though frequency can vary based on factors such as significant weather changes.

Format

  • Comprised of a series of alphanumeric codes and abbreviations for brevity, based on international standards.

Components

  • Wind: Direction and speed reported in knots.
  • Visibility: Horizontal visibility in statute miles.
  • Weather: Describes significant weather phenomena, such as rain, snow, fog, etc.
  • Sky Condition: Reports cloud cover, cloud types, and cloud height above ground level.
  • Temperature and Dew Point: Air temperature and dew point in degrees Celsius.
  • Altimeter Setting: Atmospheric pressure at sea level, providing an indication of the current pressure.

Time in Zulu

  • METAR reports provide time information in Coordinated Universal Time (UTC), commonly referred to as Zulu time in aviation.
  • Zulu time serves as a standard reference, allowing for consistency and coordination across various time zones in the aviation community.

Example:

METAR KFJK 281800Z 22010KT 10SM CLR 21/M02 A3001 RMK AO2 SLP162 T02061017

  • KFJK: Airport code for John F. Kennedy International Airport.
  • 281800Z: Day of the month (28th), time in Zulu (1800Z).
  • 22010KT: Wind from 220 degrees at 10 knots.
  • 10SM: Visibility is 10 statute miles.
  • CLR: Clear sky.
  • 21/M02: Temperature is 21°C, and dew point is -2°C.
  • A3001: Altimeter setting is 30.01 inches of mercury.
  • RMK AO2 SLP162 T02061017: Additional remarks and information about automated weather equipment, sea-level pressure, and temperature.

Access Real-time Aviation Weather with METAR Reports

Access up-to-date METAR reports by visiting https://aviationweather.gov/data/metar/, a reliable source for comprehensive and current aviation weather information.

METAR Report Acronyms: Weather Identifiers

The following abbreviations represent weather identifiers in aviation weather reports.

- RA

Slight Rain

RA

Moderate Rain

+RA

Heavy Rain

IC

Ice Crystals

SN

Moderate Snow

TS

Thunderstorm

FG

Fog

BR

Mist

GR

Hail

METAR Report Acronyms: Sky Condition

The following abbreviations represent sky conditions in aviation weather reports.

CLR

Clear Skies

BRK

Broken Clouds

SCT

Scattered Clodus

OVO

Overcast Skies

Interpreting Sky Condition Cloud Cover Heights in METAR Reports

Understand the basics of cloud cover in METAR reports, distinguishing between heights in hundreds and thousands of feet above ground level, as we break down codes like OVC030 vs OVC0300.

Low Cloud Cover Heights (Ceiling in Hundreds)

Low cloud cover heights as represented by OVC030 (clouds at 300 feet) and OVC040 (clouds at 400 feet) in METAR reports:

  • OVC030: Cloud base at 300 feet above ground level.
  • OVC040: Cloud base at 400 feet above ground level.

High Cloud Cover Heights (Ceiling in Thousands)

High cloud cover heights as represented by OVC0300 (clouds at 3,000 feet) and OVC0400 (clouds at 4,000 feet) in METAR reports:

  • OVC0300: Cloud base at 3,000 feet above ground level.
  • OVC0400: Cloud base at 4,000 feet above ground level.

METAR Report: Visual Aids and Practice

How to read metar reports

Candidates taking the FAA Part 107 exam should be prepared for questions related to METAR reports, as the ability to interpret and apply this essential aviation weather information is a key component of the examination.

Example: METAR at Denver International Airport (DEN):

This METAR reading provides a snapshot of weather conditions at Denver International Airport, including wind, visibility, precipitation, cloud cover, temperature, altimeter setting, and any relevant remarks.

Three METAR Report Examples:

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John F. Kennedy International Airport (KJFK):

METAR KFJK 281800Z 22010KT 10SM CLR 21/M02 A3001

  • 281800Z:
    • 28: Day of the month.
    • 1800Z: Time in UTC (1800 Zulu time).
  • 22010KT:
    • 220: Wind direction from 220 degrees.
    • 10: Wind speed at 10 knots.
  • 10SM:
    • 10: Visibility is 10 statute miles.
  • CLR:
    • Clear Skies: No numerical values; indicates clear sky.
  • 21/M02:
    • 21: Temperature is 21°C.
    • M02: Dew point is -2°C.
  • A3001:
    • A: Altimeter setting.
    • 3001: Altimeter setting is 30.01 inches of mercury.

Los Angeles International Airport (KLAX):

METAR KLAX 151600Z 28015G25KT 10SM OVC0200 18/15 A2987 RMK AO2 SLP113 T01780150

  • KLAX:
    • Airport code for Los Angeles International Airport.
  • 151600Z:
    • 15: Day of the month.
    • 1600Z: Time in UTC (1600 Zulu time).
  • 28015G25KT:
    • 280: Wind direction from 280 degrees.
    • 15: Wind speed at 15 knots.
    • G25KT: Gusts up to 25 knots.
  • 10SM:
    • 10: Visibility is 10 statute miles.
  • OVC0200:
    • Overcast sky at 2,000 feet.
  • 18/15:
    • 18: Temperature is 18°C.
    • 15: Dew point is 15°C.
  • A2987:
    • A: Altimeter setting.
    • 2987: Altimeter setting is 29.87 inches of mercury.

Chicago O'Hare International Airport (KORD):

METAR KORD 102200Z 05012KT 7SM -RA BKN025 08/05 A2989 RMK AO2 T00830050

  • KORD: Airport code for Chicago O’Hare International Airport.
  • 102200Z: Day of the month (10th), time in UTC (2200Z).
  • 05012KT: Wind from 050 degrees at 12 knots.
  • 7SM: Visibility is 7 statute miles.
  • -RA: Light rain.
  • SBKN025: Broken clouds at 2500 feet.
  • 08/05: Temperature is 8°C, and dew point is 5°C.
  • A2989: Altimeter setting is 29.89 inches of mercury.
  • RMK AO2 T00830050: Additional remarks and information.

Click image to expand

(Refer to Figure 12) What are the current conditions for Chicago Midway Airport (KMDW)?

A. Sky 700 feet overcast, visibility 11, occasionally 2SM, with rain.

B. Sky 700 feet overcast, visibility 1-1/2SM, rain.

C. Sky 7000 feet overcast, visibility 1-1/2SM, heavy rain.

Correct Answer: B. Sky 700 feet overcast, visibility 1-1/2SM, rain.

Description:
The order will always be in the following:

Remember it using this: Time Winds Visibly Closer To Alluring Mercury

  1. time
  2. wind direction and speed
  3. visibility in SM
  4. cloud information
  5. temperature/dew point
  6. altimeter setting in inches of mercury.

Why A and C are *not* the answers:

A. Examining the additional information, such as BOI above indicating 30SM, should have signaled that the measurement for that location should be expressed in statute miles.

C. This can be ruled out since the altitude of the cloud base always ends with two zeros, making it 700, rather than three zeros for 7000.

Click image to expand

The wind direction and velocity at KJFK is from?

A. 040° true at 18 knots.

B. 180° true at 4 knots.

C. 180° magnetic at 4 knots.

Correct Answer: B. 180° true at 4 knots.

Description:
First find where it says 18004KT, which is what describes the wind direction and velocity

(The answer will nearly always be “true” when it comes to METAR reports)