Weather & Calamities

Intermediate

Apparent Temperature (Heat Index)

How hot the air actually feels once humidity and wind are taken into account.

Formula

AT = T_a + 0.33\,e - 0.70\,w_s - 4.00

Variables

ATApparent temperature (°C)

TₐAir temperature (°C)

eWater-vapour pressure (hPa)

wₛWind speed (m/s)

Example

High humidity can make 32°C feel like 41°C

Did You Know?

Humid heat is far more dangerous than dry heat because sweat can’t evaporate to cool you.

weather heat humidity meteorology

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