Apparent Temperature Calculator: How Hot It Feels from Temperature, Humidity and Wind (Bureau of Meteorology)
The temperature it feels like, from heat, humidity and wind.
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How this calculator works
Enter the air temperature, the relative humidity and the wind speed.
The calculator finds the water vapour pressure.
It gives the apparent temperature and the difference from the air temperature.
Formulas used
- e = \frac{RH}{100}\times6.105\,e^{17.27T_a/(237.7 + T_a)}
- AT = T_a + 0.33e - 0.70\,ws - 4.00
Worked example
With the default numbers in the calculator above:
- Water vapour pressure: 25.372 hPa
- Apparent temperature (how hot it feels): 32.973 C
- Difference from the air temperature: 2.973 degrees
Change the numbers in the calculator to see the full working, every step, for your own case.
Common questions
What is apparent temperature?
A measure of how hot or cold the air feels to a person, taking humidity and wind into account as well as the air temperature.
Does the formula include the sun?
No. This is the shade version. Direct sunshine makes it feel hotter.
Why does humidity make it feel hotter?
Sweat evaporates more slowly in humid air, so the body cools less.
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Got a question about this? Ask an engineering question and get a plain-language answer with references.
Further reading: Steadman apparent temperature as published by the Australian Bureau of Meteorology.
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