# Calculate Dewpoint, Wet-bulb Temperature from Relative Humidity

A Simple online weather calculator to find the dewpoint and the wet-bulb temperature by knowing the values of relative humidity, temperature and actual station pressure. Dewpoint is the atmospheric temperature below which water droplets begin to condense and become dew. The wet-bulb temperature is the temperature a parcel of air would have if it were cooled to saturation. Using this dew point calculator, you can calculate Dewpoint, Wet-bulb Temperature from Relative Humidity.

## Calculation of Dewpoint and Wet-bulb Temperature from Relative Humidity

Code to add this calci to your website

#### Formula:

1) Dewpoint Temperature
T_{d} = [243.5 x ln(e/6.112)] / [17.67 - ln(e/6.112)]
e = (es x rh) / 100
es = 6.112 x e^{(17.67xT)/(T+243.5)}
2) Wet Bulb Temperature
E_{wg} = 6.112 x e^{(17.67xTw)/(Tw+243.5)}
eg = E_{wg} - P_{sta} x (T - T_{w}) x 0.00066 x (1 + (0.00115 x T_{w}))
T_{w} = ΣN ∀ E_{d} ≠ 0
E_{d} = e - eg

##### Where,

T_{d} = Dewpoint Temperature
T_{w} = Wet Bulb Temperature
T = Temperature
rh = Relative Humidity
P_{sta} = Actual station pressure
e = Vapor Pressure
es = Saturation Vapor Pressure
E_{d} = Vapor Pressure Difference
N = Increment by 10 and consecutive E_{d} is opposite sign, increment divide by 10. Its upto reach E_{d} is zero or absolute value of E_{d} is greater than 0.05
Calculation of *dewpoint and wet-bulb temperature* is made easier by knowing the value of relative humidity. It is used in weather forecasting.