Dew point (frost point) is a measure of atmospheric moisture. It is the temperature to which air must be cooled to reach saturation (assuming air pressure and moisture content are constant). A higher dew point indicates more moisture present in the air. It is the temperature at which dew or frost will form should the air temperature fall sufficiently.

It is the temperature at which dew or frost will form should the air temperature fall sufficiently. Other things being equal, as the temperature falls, the relative humidity rises, reaching 100% at the dew point, at least at ground level. So the air temperature can never go lower than the dew point temperature, since the relative humidity cannot exceed 100%. Relative humidity of 100% indicates the dew point is equal to the current temperature and that the air is maximally saturated with water. When the moisture content remains constant and temperature increases, relative humidity decreases.

Over 26 °C	Over 80 °F	severely high, even deadly for asthma related illnesses
24-26 °C	75-80 °F	extremely uncomfortable, fairly oppressive
21-24 °C	70-74 °F	very humid, quite uncomfortable
18-21 °C	65-69 °F	somewhat uncomfortable for most people at upper edge
16-18 °C	60-64 °F	OK for most, but all perceive the humidity at upper edge
13-16 °C	55-59 °F	comfortable
10-12 °C	50-54 °F	very comfortable
under 10 °C	under 50 °F	a bit dry for some

Calculation

Source:

wikipedia.com

Units

	C F			km/h m/s mph kt
	mm in			hPa mmHg inHg
	m ft			m km mi

Language