Definitions for "Radiation Fog"
Keywords:  fog, dew, skies, moist, night
Fog characteristically resulting when radiational cooling of the earth's surface lowers the air temperature near the ground to or below its initial dew point on calm, clear nights.
Fog formed as the ground (and objects on the ground) cool by losing long- wave infrared radiation. Conditions favorable for formation of radiation fog include light winds, clear skies, and high humidity at the surface (near or at 100 percent).
A common type of fog which forms overland on nights characterized by light wind, clear sky, and moist air in the lower levels of the atmosphere.