National Weather Service United States Department of Commerce
Meteorological Calculator
Thanks to Ron Murphy, NWS Binghamton, NY for writing the JavaScript

  Wind Chill can also be determined using this handy chart.
  Heat Index can also be determined using this handy chart.
Temperature Conversion
Enter a number then click on the appropriate number to see the result.
Fahrenheit
(o F)
Celsius
(o C)
Windchill Calculation
Enter in the air temperature (Tair) in degrees Fahrenheit and wind speed in mph, then click on the Calculate WC to compute the windchill (WC).
Tair wind
(mph)
More information about the wind chill.
Relative Humidity Calculation
Enter in the air temperature (Tair) and dew point temperature (Tdp) in degrees Fahrenheit (oF) then click on the Calculate RH to compute the relative humidity (RH).
Tair Tdp
Heat Index Calculation
Enter in the air temperature (Tair) in degrees Fahrenheit and relative humidity (RH) in percent (without the % sign), then click on the Calculate HI to compute the heat index (HI).
Tair RH Tdp=
OR
Tair Tdp RH=
More information about the Heat Index, and also about excessive heat.
Wind Speed Conversion
Input value here and then select units below ANSWERS:
mph mph
knots knots
m/s m/s
ft/s ft/s
km/h km/h
Station Pressure on next page -- >
 

 

Need more? Try the calculator at NWS El Paso