Full Line of Dew Point Meters and Monitors
The dew point is the saturation temperature for water in the air. It is the temperature at which the water vapor in a sample of air at constant barometric pressure condenses into liquid water at the same rate at which it evaporates. The dew point is associated with relative humidity. A high relative humidity implies that the dew point is closer to the current air temperature. Relative humidity of 100% indicates the dew point is equal to the current temperature and that the air is maximally saturated with water. At temperatures below the dew point, some of the moisture will condense.
The hydrocarbon dew point of a gas is a different concept from the water dew point. The hydrocarbon dew point is the temperature (at a given pressure) at which the hydrocarbon components of any hydrocarbon-rich gas mixture, such as natural gas, will start to condense out of the gaseous phase. (Source: Wikipedia)