Advection Fog

Advection fog forms when a mass of warm, moist air is transported (advected) horizontally over a colder surface, cooling the air to its dew point. Unlike radiation fog, it can form during the day or night and often requires moderate winds to move the air mass over the cold surface. A change in wind direction or air mass is typically required for it to clear.

Key Points

• •Requires the horizontal movement of warm, moist air over a cold surface.
• •Common in coastal areas where maritime air moves over cooler land or cold ocean currents.
• •Can persist in moderate winds, making it more difficult to clear than radiation fog.

Related Terms