What atmospheric condition tends to allow for more common fog development?

Fog development is primarily influenced by humidity levels and atmospheric stability. In conditions characterized by high relative humidity, particularly when they are stable, the air is typically saturated with moisture. This saturation can lead to the condensation of water vapor into tiny droplets, forming fog.

Stable atmospheric conditions mean that there is little vertical mixing of air, allowing for cooler temperatures near the ground at night or during early morning hours. When warm, moist air moves over cooler ground or water surfaces, the temperature of the air can drop, leading to condensation and fog. Hence, high relative humidity combined with stability creates an ideal environment for fog formation.

In contrast, high temperatures generally encourage evaporation and can lead to lower humidity levels, which are less conducive to fog. Low humidity diminishes the amount of moisture available for condensation, making fog formation less likely. High wind speeds create turbulence, mixing air layers and preventing the air from cooling sufficiently to form fog. Therefore, stable conditions with high relative humidity are crucial for common fog development.