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Meteorology and Weather Interpretation Flashcards

7 cards from real CPL practice questions. Tap to flip, then mark Knew It or Still Learning — missed cards come back until you master them.

Read the first 7 Meteorology and Weather Interpretation flashcards as text

  1. Mountain wave turbulence is most likely when wind direction is approximately how many degrees relative to the ridge?

    Answer: Perpendicular (60–90°) to the ridge

    Mountain waves are most pronounced when wind blows nearly perpendicular (within 30° of 90°) to the mountain ridge at sufficient speed.

  2. What does 'SPECI' designate when issued between routine METAR observations?

    Answer: A special weather observation reporting a significant change in conditions

    A SPECI (Special Meteorological Report) is issued between routine METARs when significant weather changes occur, such as visibility dropping below a minimum or ceiling lowering rapidly.

  3. Which atmospheric condition produces the longest duration and most widespread icing?

    Answer: Frontal stratus and nimbostratus associated with a warm front

    Warm fronts produce extensive layers of stratus and nimbostratus that can cover hundreds of miles and maintain icing conditions for many hours.

  4. What is 'virga'?

    Answer: Precipitation that evaporates before reaching the ground

    Virga is precipitation (rain or ice crystals) that falls from a cloud but evaporates or sublimates before reaching the surface.

  5. A SIGMET for volcanic ash advises avoidance of a region. Why is volcanic ash especially hazardous to jet engines?

    Answer: It melts in combustion chambers and re-solidifies on turbine blades, causing flameout

    Volcanic ash particles melt at jet combustion temperatures and then resolidify on the cooler turbine blades, causing power loss or engine flameout.

  6. What is the purpose of the AIRMET Sierra (SIGMET for IFR)?

    Answer: Warn of widespread IFR conditions or mountain obscurement affecting VFR aircraft

    AIRMET Sierra (S) is issued for widespread IFR conditions (ceiling <1,000 ft and/or visibility <3 SM) or mountain obscurement, primarily affecting light aircraft.

  7. What effect does a high-pressure center (anticyclone) typically have on surface winds in the Northern Hemisphere?

    Answer: Winds flow clockwise and outward away from the center

    In the Northern Hemisphere, Coriolis effect causes anticyclonic flow to be clockwise with diverging (outward-spiraling) surface winds.