CPL Meteorology · Practice

During a pre-flight weather briefing, the forecaster mentions an 'upper trough' is positioned over your route. What does an upper trough cause and what weather should you anticipate?

• A.Upper troughs are below FL100
• B.Upper trough: a dip in the upper-level isobaric pattern.
• C.Upper trough = area of high pressure → stable weather, no turbulence
• D.Upper troughs only affect temperatures