What weather phenomena have to be expected around an upper-level trough?

Question

Question PPL(A) - Private Pilot License - Meteorology

QuizVDS · Accepted Answer

Development of showers and thunderstorms (Cb)

QuizVDS · Answer

Calm wind, forming of shallow cumulus clouds

QuizVDS · Answer

Calm weather, formation of lifted fog layers

QuizVDS · Answer

Formation of high stratus clouds, ground-covering cloud bases

Id 87 - PPL(A) EN - What weather phenomena have to be expected around an upper-level trough?