Meteorology
Core framework
Meteorology questions test your reading of the atmosphere: pressure systems, fronts, clouds, visibility and wind. Know the standard atmosphere (ISA: 15 °C at sea level, lapse rate 1.98 °C/1,000 ft), and how pressure, temperature and humidity affect altimetry and performance.
Concepts to master
Frontal systems (cold, warm, occluded) and their associated weather. Cloud types and their hazards: cumulonimbus (thunderstorms, icing, turbulence, microbursts), stratiform cloud (icing, low visibility). Understand icing types (rime, clear) and their formation conditions. Know wind shear, mountain waves and the foehn effect. Decode METAR and TAF: wind, visibility, cloud base, temperature/dewpoint, QNH.
Traps
- Confusing QNH (altitude when set at aerodrome) with QFE (height above reference) and QNE (standard pressure).
- Forgetting that temperature above ISA makes the altimeter over-read (true altitude higher than indicated).
- Mixing rime (small droplets, low temp) with clear (large droplets, near 0 °C) icing.
- Assuming thunderstorms are only a summer phenomenon - they occur year-round.
Rule of thumb
"High to low, look out below." Flying from high pressure to low pressure (or warm to cold) without adjusting the altimeter means your true altitude is lower than indicated.
Worked example
A METAR shows QNH 1003 hPa. If you fly toward a lower-pressure area without resetting, the altimeter reads high relative to true altitude - terrain clearance is reduced. Reset to the local QNH.