ATPL Canadian Meteorology, Radio Aids to Navigation, and Flight Planning (SAMRA) 2026 – 400 Free Practice Questions to Pass the Exam

As a cold front passes, the dew point typically falls. This occurs because a cold front brings a mass of colder, drier air into an area; as this colder air overtakes the warmer, moist air that was present, the humidity levels decrease. When the temperature drops with the arrival of the cold front, the moisture-holding capacity of the air also decreases, leading to a reduction in the dew point. A lower dew point indicates that there is less moisture in the air, making it drier than before the front passed.

In contrast, a steady dew point would imply no significant change in moisture content, while a rise in the dew point would suggest an influx of warmer, more humid air, which is contrary to the typical behavior of a cold front. Fluctuations might occur momentarily due to localized conditions, but the predominant effect of a cold front is to lower the dew point as it replaces the moist air with cooler and drier air.