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Heat Index

The Heat Index (HI) is defined as the temperature the human body perceives in shady conditions when perspiration is limited due to increased relative humidity.

thermofeel computes the HI with two methods: Heat Index Simplified and Heat Index Adjusted.

More information:

How to use

Simplified Heat Index

You need 2 m air temperature in Kelvin and relative humidity as a percentage. Please use NumPy arrays.

It returns the HI in Kelvin.

calculate_heat_index_simplified(2m_temperature, relative_humidity_percent)

Adjusted Heat Index

You need 2 m air temperature and 2 m dew point temperature in Kelvin. Please use NumPy arrays.

It returns the HI in Kelvin.

calculate_heat_index_adjusted(2m_temperature, 2m_dew_point_temperature)

Interpret the output

The HI is described in terms of danger of heat-related illnesses (NOAA/NWS classification):

Heat Index (°C) Risk
27 – 32 Caution
32 – 39 Extreme caution
39 – 51 Danger
≥ 51 Extreme danger