National Weather Service United States Department of Commerce

Fire Weather Concerns; Record Warmth Spreads

The Plains to the mid-Mississippi Valley continue with warm and dry conditions. Any fires that initiate could spread quickly. The warm temperatures will expand across the Southern Plains into the Southwest where numerous records are expected through the weekend. Meanwhile, a cold front will move southward across the northern Plains and Great Lakes region where some snow will develop this weekend. 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?