National Weather Service United States Department of Commerce

Heat Builds in the West; Extremely Critical Fire Weather in the Northwest

A heat wave over the Southwest will intensify this week, peaking and expanding into the Intermountain West and northern High Plains this weekend. Critical to extremely critical fire weather conditions are forecast from the Northwest and the northern Great Basin this weekend. Particularly Dangerous Situation Red Flag Warnings have been issued. Read More >

Vapor Pressure

by Tim Brice and Todd Hall
 
 
Enter a temperature or a dewpoint or both:
Vapor Pressure
If you want the saturated vapor pressure enter the air temperature:  saturated vapor pressure:
  Fahrenheit Celsius Kelvin mb in of HG mm HG 
hPA kPA lbs per square in
If you want the actual vapor pressure enter the dewpoint:  actual vapor pressure:
  Fahrenheit Celsius Kelvin mb in of HG mm HG 
hPA kPA lbs per square in
If you enter both the air temperature and the dewpoint you'll get a bonus answer.  relative humidity - requires both temp and dewpoint
  %

 

What is the formula for the vapor pressure script?