Wednesday, November 4, 2026 · Captain's Challenge
The Captain's Challenge.
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Capt. Mike: Here's that evening's Captain's Challenge. Tap your answer.
Persistent, dense fog frequently affects operations at a coastal airport in Newfoundland, particularly in spring and early summer. Which fog type is most likely responsible, and what is the formation mechanism?
The answer
1Advection fog — warm moist air cooled over the cold Labrador Current
Explanation
Warm, moist air moving north from the Gulf Stream passes over the cold water of the Labrador Current; its lower layers cool to the dew point and fog forms. Because it is produced by the air's movement over a cold surface rather than by nightly cooling, this advection fog can be extensive and persist for days. It is most frequent in spring and early summer, when the contrast between the warm air and the cold sea is greatest.
Memory tip: Newfoundland fog = warm Gulf air over the cold Labrador Current = advection fog.
Source
Air Command Weather Manual (TP 9352E) — fog (TC-recommended study material, TP 13524E)
Taught in: IATRA › Advanced MeteorologyThis question is from the IATRA course, which teaches every IATRA subject and drills it like this. Unlock all 6 chapters with their quizzes (90 questions), and 6 full-length IATRA mock exams.
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