CPL Meteorology · Practice

During a pre-flight weather briefing, you note that the MSLP at your departure aerodrome has fallen 6 hPa in the past 3 hours (from 1018 hPa to 1012 hPa). What synoptic situation does this rate of pressure fall most likely indicate, and what weather should you anticipate?

• A.A 6 hPa fall in 3 hours is within normal diurnal (tidal) pressure variation and has no synoptic significance
• B.Pressure falls only occur when an upper-level trough is directly overhead
• C.A 6 hPa fall in 3 hours indicates a ridge is building
• D.A rapidly deepening low-pressure system is approaching