Learning Objective 050.04.02.01.03: Name the factors that generally contribute to the formation of fog and mist.

Fog (FG) occurs when the horizontal visibility is reduced to less than 1 000 m and is caused by small water droplets with a diameter less than 0.5 mm floating in the air.

Mist (BR) is the same phenomenon as fog, but in this case, visibility is over 1 000 m but less than 5 000 m.

"Haze" visibility is reduced by extremely small solid particles (such as sand, dust or smoke). Reported if the visibility is reduced below 1000 m.