Frontal fog is commonly associated with which type of weather systems?

Frontal fog typically forms in the vicinity of warm or cold fronts, which are weather systems characterized by the boundary between different air masses. When warm air is forced to rise over a colder air mass, it cools and condenses, creating fog. This process is amplified when the warm, moist air interacts with the cooler surface temperatures associated with these fronts.

With warm fronts, as the warm air gradually ascends over the cooler air, it can lead to widespread stratus clouds and fog. On the other hand, cold fronts can also produce fog, particularly in cases where warm air is lifted rapidly due to the more aggressive displacement of warm air aloft.

The formation of frontal fog is directly linked to the changes in temperature and humidity that come with the passage of these fronts, making them the principal systems where this type of fog is observed.