National Weather Service United States Department of Commerce

Dangerous Heat and Humidity Building from the Plains to the East Coast

Strengthening high pressure will bring much above normal high and low temperatures. Widespread highs in the 90s to 100 combined with dewpoints surging into the mid and upper 70s will create heat indices as high as 110 through this weekend. In addition, overnight temperatures in the 70s to low 80s will reduce the ability of the body to recover from daytime heating. Read More >

Relative Humidity

by Tim Brice and Todd Hall
 
 
Enter a temperature, relative humidity and actual station pressure
 
Temperature:  wet-bulb  unit

dewpoint

Fahrenheit Celsius Kelvin Fahrenheit
RH: Celsius
% Kelvin
Enter your actual station pressure (not the altimeter setting):  
in of mercury mm of mercury millibars (hPA)  

 

What is the formula for the relative humidity script?