How To Read METAR Reports: A Complete Guide for PPL Students
As a student pilot working toward your Private Pilot License, understanding weather information is crucial for safe flight operations. Among the various weather reports available, METAR (Meteorological Aerodrome Report) stands as one of the most important tools in your aviation toolkit.
What is a METAR Report?
A METAR is a standardized international weather observation code used to report surface weather conditions at airports and meteorological stations worldwide. These reports are typically issued every 30 minutes or hourly, providing pilots with current weather conditions essential for flight planning and safety decisions.
Important Note: Under EASA regulations, pilots must demonstrate competency in interpreting meteorological information, including METAR reports, as part of their theoretical knowledge requirements.
Understanding METAR Format Structure
METAR reports follow a specific format that remains consistent globally. Let's break down a typical METAR report:
Example METAR: `EGLL 121220Z 24008KT 9999 FEW035 SCT250 06/M02 Q1023 NOSIG=`
Station Identifier (ICAO Code)
The first four letters identify the reporting station using the International Civil Aviation Organization (ICAO) code system.- EGLL = London Heathrow Airport
- KJFK = John F. Kennedy International Airport
- LFPG = Charles de Gaulle Airport, Paris
Date and Time Group
The next six digits represent the day of the month and time in UTC (Coordinated Universal Time).- 121220Z = 12th day of the month at 12:20 UTC
- The "Z" indicates Zulu time (UTC)
Study Tip: Always remember that METAR times are in UTC, not local time. This is crucial for flight planning across time zones.
Decoding Wind Information
Wind information follows immediately after the time group and includes:
Wind Direction and Speed
- 24008KT = Wind from 240° at 8 knots
- First three digits: wind direction in degrees magnetic
- Next two digits: wind speed
- KT = knots (other units may include MPS for meters per second)
Variable Wind Conditions
- VRB03KT = Variable wind direction at 3 knots
- 24008G15KT = Wind from 240° at 8 knots, gusting to 15 knots
- 240V300 = Wind direction varying between 240° and 300°
Calm Conditions
- 00000KT = Calm winds (less than 1 knot)
Visibility Information
Visibility is reported in meters or statute miles, depending on the country:
Metric System (Most International Airports)
- 9999 = Visibility 10 kilometers or more
- 0800 = Visibility 800 meters
- //// = Visibility not available
Imperial System (US Airports)
- 10SM = 10 statute miles visibility
- 1/2SM = Half statute mile visibility
Weather Phenomena Codes
METAR reports use specific codes to describe current weather conditions:
Intensity Indicators
- - = Light intensity
- (no symbol) = Moderate intensity
- + = Heavy intensity
Common Weather Phenomena
- RA = Rain
- SN = Snow
- FG = Fog
- BR = Mist
- TS = Thunderstorm
- DZ = Drizzle
- SH = Showers
Combined Examples
- -RA = Light rain
- +TSRA = Heavy thunderstorm with rain
- SHRA = Rain showers
Cloud Information
Cloud coverage and heights are reported using specific abbreviations:
Cloud Coverage
- SKC = Sky clear (no clouds)
- FEW = Few clouds (1/8 to 2/8 coverage)
- SCT = Scattered clouds (3/8 to 4/8 coverage)
- BKN = Broken clouds (5/8 to 7/8 coverage)
- OVC = Overcast (8/8 coverage)
Cloud Heights
Cloud heights are given in hundreds of feet above ground level (AGL):- FEW035 = Few clouds at 3,500 feet AGL
- SCT250 = Scattered clouds at 25,000 feet AGL
- BKN008 = Broken clouds at 800 feet AGL
Special Cloud Types
- TCU = Towering cumulus
- CB = Cumulonimbus
Temperature and Dewpoint
Temperature and dewpoint are reported in degrees Celsius:
- 06/M02 = Temperature 6°C, dewpoint -2°C (M indicates minus)
- M05/M08 = Temperature -5°C, dewpoint -8°C
Weather Planning Tip: When temperature and dewpoint are close (within 2-3°C), expect fog or low cloud formation, especially during cooling periods.
Pressure Information (QNH)
Atmospheric pressure is crucial for altimeter settings:
- Q1023 = QNH 1023 hectopascals (millibars)
- A2992 = 29.92 inches of mercury (US format)
Trend Information
METAR reports may include trend forecasts:
- NOSIG = No significant change expected in next 2 hours
- TEMPO = Temporary conditions expected
- BECMG = Becoming (permanent change expected)
Practical Application for Flight Planning
Pre-flight Weather Assessment
Decision-Making Process
- VFR Minimums: Ensure visibility and cloud clearance meet regulatory requirements
- Personal Minimums: Apply your own stricter limits based on experience
- Alternate Planning: Always have backup airports with suitable weather
Common Student Mistakes to Avoid
Regulatory Requirements
Under EASA Part-FCL, PPL candidates must demonstrate knowledge of:
- Meteorological information interpretation
- Weather decision-making for VFR flight
- Use of meteorological services
Practice and Proficiency
To master METAR interpretation:
Conclusion
Mastering METAR interpretation is essential for safe flight operations and successful completion of your PPL examinations. These standardized reports provide crucial information for weather-related decision making throughout your aviation career.
Remember that METAR reports represent current conditions at the time of observation. Always consider trends, forecasts, and your personal minimums when making flight decisions. Weather interpretation skills develop with experience, so practice regularly and never hesitate to seek clarification from meteorological services or experienced pilots when in doubt.
Final Reminder: When in doubt about weather conditions, the safest decision is often to wait for better conditions or seek additional information from qualified meteorological sources.