Migrating from Thermal Comfort¶

This page maps every Thermal Comfort sensor to its Weather Station Core equivalent and provides a 5-step migration procedure.

Thermal Comfort (last release: February 2025) provides heat-stress comfort indices as a template-free HA integration. Weather Station Core includes all of those indices and extends them significantly.

Entity mapping¶

Thermal Comfort entity IDs follow sensor.<name>_<metric>. ws_core uses sensor.ws_<metric> (or your chosen prefix, set in step 1 of setup).

Thermal Comfort sensor	ws_core equivalent	Notes
`sensor.<name>_apparent_temperature`	`sensor.ws_feels_like`	Same formula: Australian BOM / Steadman (1994). Values match within 0.1 °C for identical inputs.
`sensor.<name>_heat_index`	`sensor.ws_heat_index`	Same formula: NWS Rothfusz regression. Active when T ≥ 27 °C and RH ≥ 40%.
`sensor.<name>_heat_index_perception`	Attribute `level` on `sensor.ws_heat_index`	Classification is in the sensor attribute, not a separate entity.
`sensor.<name>_humidex`	`sensor.ws_humidex`	Same formula: Environment Canada (Masterton & Richardson 1979).
`sensor.<name>_humidex_perception`	Attribute `level` on `sensor.ws_humidex`	See heat_index_perception note above.
`sensor.<name>_absolute_humidity`	`sensor.ws_absolute_humidity`	Same formula: ideal gas law for water vapour.
`sensor.<name>_dew_point`	`sensor.ws_dew_point`	ws_core uses Magnus formula (Alduchov & Eskridge 1996). Typical difference: < 0.2 °C.
`sensor.<name>_frost_point`	`sensor.ws_frost_point`	ws_core uses Buck (1981) ice constants below 0 °C — more physically accurate.
`sensor.<name>_wind_chill`	`sensor.ws_wind_chill`	Same formula: WMO/NWS 2001. Active when T ≤ 10 °C and wind > 1.34 m/s.
`sensor.<name>_thw_index`	`sensor.ws_thw_index`	Same formula: Davis Instruments THW index.
`sensor.<name>_thsw_index`	`sensor.ws_thsw_index`	Requires a solar radiation sensor mapped in ws_core.
`sensor.<name>_moist_air_enthalpy`	No direct equivalent	The `sensor.ws_vpd` sensor covers related HVAC/greenhouse use cases.
`sensor.<name>_relative_strain_index`	No direct equivalent	Not in ws_core. Keep Thermal Comfort alongside ws_core if needed.
`sensor.<name>_summer_simmer_index`	No direct equivalent	Not in ws_core. Keep Thermal Comfort alongside ws_core if needed.

Additional sensors ws_core provides beyond Thermal Comfort¶

ws_core sensor	Description
`sensor.ws_utci`	UTCI (Universal Thermal Climate Index, Bröde 2012) — the WHO standard
`sensor.ws_wbgt`	Wet Bulb Globe Temperature
`sensor.ws_vpd`	Vapour Pressure Deficit (greenhouse, irrigation)
`sensor.ws_delta_t`	Delta-T spray application index
All fire danger sensors	FWI, FFDI, FFWI (see Fire Danger)
Nowcast sensors	`ws_minutes_until_rain`, etc.
ET₀ sensors	`ws_et0_daily`, `ws_et0_pm_daily`
Lightning sensors	Strike count, distance, clearance

Formula differences¶

Metric	Thermal Comfort	ws_core	Impact
Dew point	August-Roche-Magnus	Magnus, Alduchov & Eskridge (1996)	< 0.2 °C difference
Frost point	Same formula as dew point always	Buck (1981) ice constants below 0 °C	More accurate below 0 °C
Apparent temperature	Steadman (1994) BOM	Steadman (1994) BOM	Identical
Heat index	Rothfusz (1990)	Rothfusz (1990)	Identical
Wind chill	WMO/NWS 2001	WMO/NWS 2001	Identical

5-step migration¶

Step 1: Install ws_core alongside Thermal Comfort¶

Install Weather Station Core via HACS without removing Thermal Comfort. Both can run simultaneously. This lets you verify that ws_core values match before switching automations.

Step 2: Enable comfort indices¶

In ws_core: Settings → Devices & Services → Weather Station Core → Configure → Features → Comfort Indices.

Or toggle switch.ws_enable_comfort_indices on the device page.

Step 3: Verify values¶

Open Developer Tools → States and compare: - sensor.<tc_name>_apparent_temperature vs sensor.ws_feels_like - sensor.<tc_name>_heat_index vs sensor.ws_heat_index - sensor.<tc_name>_dew_point vs sensor.ws_dew_point

Differences of < 0.5 °C for all temperature sensors are expected. Larger differences indicate a unit mismatch or input sensor issue.

Step 4: Update automations and dashboards¶

Replace Thermal Comfort entity IDs with ws_core equivalents using the table above. Do a find-and-replace on dashboard YAML for each entity ID pair.

Step 5: Remove Thermal Comfort¶

Once automations and dashboards are confirmed working: 1. Settings → Devices & Services → Thermal Comfort → Delete 2. Restart Home Assistant

Handling missing equivalents¶

Three Thermal Comfort sensors have no ws_core equivalent: moist_air_enthalpy, relative_strain_index, summer_simmer_index.

Options: - Keep Thermal Comfort installed alongside ws_core (they do not conflict) - Recreate them as HA template sensors using the formulas from Thermal Comfort's source code (custom_components/thermal_comfort/sensor.py)

Indoor-only use case¶

ws_core is designed for outdoor weather station data. If you use Thermal Comfort only with indoor temperature and humidity sensors (no outdoor weather station), ws_core's outdoor weather mode is not a direct replacement.

ws_core does have an Indoor Sensors group (enable_indoor) for monitoring indoor comfort alongside outdoor weather, but it still requires a full outdoor station for the core integration to function.