Meteorology

Fog

Definition

A cloud at ground level that reduces visibility below 1 kilometer. Types include radiation fog (nighttime cooling), advection fog (warm air over cold surface), and upslope fog. A major cause of IFR conditions.

Related Terms

Visibility

The greatest distance at which objects can be seen and identified. Reported in s...

Ceiling

The height above ground level of the lowest broken or overcast cloud layer. Ceil...

Instrument Flight Rules(IFR)

Flight rules requiring navigation solely by reference to flight instruments. IFR...

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