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Temperature Conversion
Enter a number then click on the appropriate number to see the result.
Fahrenheit (F)

 

 

Celsius (C)

Wind Chill/Temperature Index Calculation in degrees Fahrenheit

Enter in the air temperature ( Tair ) in degrees Fahrenheit and wind speed in mile per hour ( mph ), then click on the Calculate WC to compute the windchill ( WC ).

Tair F mph

 

 

Wind Chill/Temperature Index Calculation in degrees Celsius

Enter in the air temperature ( Tair ) in degrees Celsius and wind speed in miles per hour, then click on the Calculate WC to compute the windchill ( WC ).

Tair C mph
Relative Humidity Calculation using degrees Fahrenheit

Enter in the air temperature ( Tair ) and dew point temperature ( Tdp) in degrees Fahrenheit ( °CF ) then click on the Calculate RH to compute the relative humidity ( RH ).
Tair in °F Tdp in °F RH
Tair
Tdp

 

 

Relative Humidity Calculation using degrees Celsius

Enter in the air temperature ( Tair ) and dew point temperature ( Tdp) in degrees Celsius ( °CF ) then click on the Calculate RH to compute the relative humidity ( RH ).
Tair in °C Tdp in °C RH
Tair
Tdp
Heat Index Calculation

Valid entries are, air temperatures greater than 80 °F ( 27 °C ), dew point temperatures greater than 65 °F ( 12 °C ), and relative humidities higher than 40 percent.
 
in Celsius

Enter in the air temperature ( Tair ) and the dew point temperature ( Tdp ) in degrees Celsius, then click on the Calculate HI to compute the heat index ( HI).
Tair in °C Tdp in °C RH =

 

in Fahrenheit

Enter in the air temperature ( Tair ) the dew point temperature ( Tdp ) in degrees Fahrenheit, then click on the Calculate HI to compute the heat index ( HI).

 

Tair in °F Tdp in °F RH =

 

in Celsius

Enter in the air temperature ( Tair ) in degrees Celsius and relative humidity ( RH ) in percent ( without the % sign ), then click on the Calculate HI to compute the heat index ( HI ).

 

Tair in °C RH Tdp =

 

in Fahrenheit

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 in °F RH Tdp =

 

Additional Information

  • Fahrenheit - The standard scale used to measure temperature in the United States. On this scale, the freezing point of water is 32°F and the boiling point is 212°F. To convert a Celsius temperature to Fahrenheit, multiply it by 9/5 and then add 32: °F = (°C * 9/5) + 32
  • Celsius - The standard scale used to measure temperature in most areas outside the United States. On this scale, the freezing point of water is 0°C and the boiling point is 100°C. To convert a Fahrenheit temperature to Celsius, subtract 32 from it and then multiply by 5/9: °C = (°F - 32) * 5/9
  • Relative Humidity - A dimensionless ratio, expressed in percent, of the amount of atmospheric moisture present relative to the amount that would be present if the air were saturated. Since the latter amount is dependent on temperature, relative humidity is a function of both moisture content and temperature. As such, relative humidity by itself does not directly indicate the actual amount of atmospheric moisture present. In this application the equation below is used where T is the air temperature in Celsius and the Td is the dew point temperature in Celsius.

RH equation.

  • Windchill -  The windchill temperature is how cold people and animals feel when outside. Windchill is based on the rate of heat loss from exposed skin caused by wind and cold. As the wind increases, it draws heat from the body, driving down skin temperature and eventually the internal body temperature. Therefore, the wind makes it FEEL much colder. If the temperature is 0 degrees Fahrenheit and the wind is blowing at 15 mph, the windchill is -19 degrees Fahrenheit. At this windchill temperature, exposed skin can freeze in 30 minutes.  Read More
  • Heat Index - The Heat Index (HI) or the "Apparent Temperature" is a measure of how hot it feels when the Relative Humidity (RH) is added to the actual air temperature. Read More