Heat Index / Apparent Temperature / Feels Like Temperature


Several solutions were discussed here and on other threads so I tried a few. Here are my results in case anyone is interested.

  1. Outdoor Feels Like (Feels Like Suite) @ masterkenobi
  2. SensorX Real Feel @ Petrica
  3. Limych Feels Like @ Limych

They all follow nearly the exact same pattern but have significant offsets. Not to criticize anyone’s work, but IMO “SenxorX Real Feel” felt the closest to my expectation of temperature experience.


Sorry to spoil the party, but it seems any computation should consider the impact of humidity on insulating value of clothing…

Perhaps heat index and apparent temperature are relatively different concepts with different scope of application ?..

First about Heat Index:
Heat Index shows how much hotter the air seems to be than the ambient dry-bulb temperature due to the influence of humidity.
I found that the formula of the multiple regression analysis conducted by Lans P. Rothfusz is limited by temperature >~27C. Accordingly, for lower temperatures, the result may have large discrepancies relative to the original tables by Steadman. Although a simplified expression ( HI = 0.5 * {T + 61.0 + [(T-68.0)1.2] + (RH0.094)}) is given to circumvent this limitation.

On the other hand, the Apparent temperature has a wider range of acceptable values of dry-bulb temperature values (>20C).

Therefore, it may make sense to combine formulas. However, it should be borne in mind that the heat index / apparent temperature graphs intersect at different temperatures.

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