frontal fog

meteorology

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Last updated

June 17, 2026

Quick Summary

Frontal fog is a type of fog that forms near weather fronts. It occurs when raindrops falling from warmer air above a frontal surface evaporate into cooler air near the Earth's surface. This process increases the moisture content of the cooler air, leading to saturation and the formation of fog. Fog, in general, is a cloud of small water droplets near ground level that reduces horizontal visibility to less than 1,000 meters (3,281 feet). It forms when air becomes saturated with moisture, typically through cooling or the mixing of air masses.12

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fog
Frontal fog forms near a front when raindrops, falling from relatively warm air above a frontal surface, evaporate into cooler air close to the Earth’s surface and cause it to become saturated.
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Frontal fog forms near a front when raindrops, falling from relatively warm air above a frontal surface, evaporate into cooler air close to the Earth’s surface and cause it to become saturated.
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How Does Fog Form?
Frontal fog forms near weather fronts when raindrops from warmer air above evaporate into cooler air near the Earth’s surface, increasing its moisture content and leading to saturation. Radiation fog forms over land on calm, clear nights when the ground loses heat through radiation and…
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Frontal fog forms near weather fronts when raindrops from warmer air above evaporate into cooler air near the Earth’s surface, increasing its moisture content and leading to saturation. Radiation fog forms over land on calm, clear nights when the ground loses heat through radiation and…
Read More