Real Feel template sensor (Celsius)

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1

(only tested for Celsius scale)

Been using, for some time, Real Feel template sensors based on the temperature and relative humidity (https://www.wpc.ncep.noaa.gov/html/heatindex_equation.shtml) gathered by different devices around the house - DHT11/22 sensors mounted on NodeMCU, BLE and RF433 sensors. Also, I’ve seen this implemented in BRUH sensor https://github.com/bruhautomation/ESP-MQTT-JSON-Multisensor/pull/24/commits/d7885aad8eeeac5217c96732d92fc6cbbb53c04c.

However, it didn’t felt “real” (aprox. 3-4 degrees above during winter and 1-2 below in the summer) and I found WBGT formula (http://www.bom.gov.au/info/thermal_stress/#apparent) more accurate.

For calibration this can be plotted into an Excel table with the following formula: =0.567*temp+0.393*hum/100*6.105*EXP(17.27*temp/(237.7+temp))+3.94

- platform: template
  sensors:
    sensorx_real_feel:
      friendly_name: "SensorX Real Feel"
      value_template: '{{(0.567 * states.sensor.sensorx_temperature.state|float + 0.393 * (states.sensor.sensorx_humidity.state|float / 100 * 6.105 * e ** (17.27 * states.sensor.sensorx_temperature.state|float / (237.7 + states.sensor.sensorx_temperature.state|float ) )) + 3.94) | round(2) }}'
      unit_of_measurement: '°C'
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2

Was wanting to do this exact same thing. Cheers for this.

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nice, using a template sensor for apparent temp myself, Ill add this to see the difference, thx! rewrote it a bit for readability:

{% set temp = states('sensor.br_temperature')|float %}
{% set humidity = states('sensor.br_humidity')|float %}
{{(0.567 * temp + 0.393 * (humidity/ 100 * 6.105 * e ** (17.27 * temp / (237.7 + temp ) )) + 3.94) | round(2) }}
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4

I cant seem to get this to work properly

Screenshot 2021-07-27 at 9.20.03 pm
Screenshot 2021-07-27 at 9.20.03 pm2208×640 94.2 KB

My humidity reading is currently 62.6% and my temperature is 23.6C but its returning a feel like of 5.44C any ideas on where i’m going wrong

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I think that the temperature sensor doesn’t provide a numeric value thus it is brought as nil in the formula (if you replace temperature with 0 and humidity with 62.6 you will get that 5.44).

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6

Sorted, thank you.

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Is it normal for the “real feel” to be BELOW the normal temperature? I’m at 25°C @ 40% humidity, and the real feel is showing as 23°C. Is that even possible?

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You can check the footnotes on the source.

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