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Weather theoryQuestion 341 of 934

An air mass moves over a colder surface. What does this create?

  1. An unstable air mass with good surface visibility
  2. Convective currents with scattered showers aloft
  3. Strong turbulence in the lowest 3,000 feet of air
  4. A stable air mass with poor surface visibility
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Correct answer: A stable air mass with poor surface visibility

Smoke, dust, and other particles stay trapped near the surface. Low stratus and fog can form.

Source: Pilot's Handbook of Aeronautical Knowledge (FAA-H-8083-25C), Chapter 12: Weather Theory — Air Masses and Fronts, page 302

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Questions last reviewed: 18 October 2026