Felt Temperature

An easy-to-use “felt temperature” sensor for Home Assistant based on a simplified UTCI‑like approach. It combines temperature, humidity and (optionally) wind to estimate how the weather feels.

This is a pragmatic approximation, not the official UTCI. It’s built for simple setup and fast results.

Requirements

• Temperature and relative humidity sources are required.
• Wind source is optional (recommended for better realism).
• You can either select one weather.* entity (which provides all values) or choose separate sources for each.

Installation

1. Copy this custom component into custom_components/felt_temperature/ or install via HACS (if available).
2. Restart Home Assistant.
3. Add the integration: Settings → Devices & Services → Add Integration → Felt Temperature.

Configuration

You can configure the integration in two ways:

1. Weather mode (recommended)

• Select a single weather.* entity (e.g. weather.home).
• The integration reads temperature, humidity and wind from the weather entity.
• If wind is not available, it will be ignored (treated as 0 m/s).

2. Separate sources

• Select a temperature source (sensor/climate/weather) – required.
• Select a humidity source (sensor/climate/weather) – required.
• Select a wind source (sensor/weather) – optional.

Tips

• Prefer outdoor sensors for an outdoor felt temperature.
• Ensure correct units: °C, %, and m/s (conversion is handled when possible).

Entity attributes

• temperature_source / temperature_source_value
• humidity_source / humidity_source_value
• wind_speed_source / wind_speed_source_value

How it works (short)

The integration uses a simple equation inspired by apparent temperature concepts:

felt ≈ Ta + 0.33 * e - 0.70 * Va - 4.00

where e is vapor pressure derived from temperature and RH, Va is wind speed in m/s, and Ta is air temperature in °C. This is intentionally simplified for reliability and performance.

Troubleshooting

• Sensor shows no value: make sure temperature and humidity sources are available and not unknown/unavailable.
• Wind is ignored: wind source missing or not providing a numeric value.
• Odd values: verify units and that sensors are outdoor if that’s your use case.

Notes

• This is an approximation of felt temperature and not the full UTCI implementation.
• Contributions and issues: see the issue tracker.