Dew Point

Dew Point is the temperature to which air must be cooled (at constant pressure) for water vapor to condense into liquid water. When the air temperature equals the dew point, the air is saturated and fog, clouds, or precipitation may form.

• Reported in METAR alongside temperature (e.g., 24/18 means temp 24°C, dew point 18°C)
• Small temperature/dew point spread indicates high humidity and potential for fog or low clouds
• When spread is 2°C or less, fog formation is likely
• Important for calculating density altitude and carburetor icing risk