What type of fog is associated with a temperature drop at night near the dew point?

Radiation fog forms during the night when the ground cools rapidly due to radiation heat loss, particularly under clear skies. As the air near the surface cools, especially when the temperature drops to the dew point, moisture in the air condenses into tiny water droplets, creating fog. This phenomenon is most common in valleys and low-lying areas where cooler air settles.

The ideal conditions for radiation fog include calm winds and clear skies, which allow for significant cooling to occur. This type of fog typically dissipates after the sun rises and warms the ground, causing the air temperature to rise back above the dew point and evaporate the fog.

The other types of fog listed have different formation processes. Advection fog occurs when warm, moist air moves over a cooler surface, leading to condensation. Steam fog forms when cold air passes over warm water, causing evaporation. Frontal fog develops along weather fronts when warm and cold air masses meet, causing cooling and condensation without the specific temperature drop associated with radiation fog.