diff --git a/homeassistant/components/tomorrowio/sensor.py b/homeassistant/components/tomorrowio/sensor.py
index b2179cd60f5..1f3bb74b686 100644
--- a/homeassistant/components/tomorrowio/sensor.py
+++ b/homeassistant/components/tomorrowio/sensor.py
@@ -39,6 +39,7 @@ from homeassistant.core import HomeAssistant
 from homeassistant.helpers.entity_platform import AddEntitiesCallback
 from homeassistant.util import slugify
 from homeassistant.util.unit_conversion import DistanceConverter, SpeedConverter
+from homeassistant.util.unit_system import IMPERIAL_SYSTEM
 
 from . import TomorrowioDataUpdateCoordinator, TomorrowioEntity
 from .const import (
@@ -327,11 +328,9 @@ class BaseTomorrowioSensorEntity(TomorrowioEntity, SensorEntity):
         )
         self._attr_extra_state_attributes = {ATTR_ATTRIBUTION: self.attribution}
         if self.entity_description.native_unit_of_measurement is None:
-            self._attr_native_unit_of_measurement = (
-                description.unit_metric
-                if hass.config.units.is_metric
-                else description.unit_imperial
-            )
+            self._attr_native_unit_of_measurement = description.unit_metric
+            if hass.config.units is IMPERIAL_SYSTEM:
+                self._attr_native_unit_of_measurement = description.unit_imperial
 
     @property
     @abstractmethod
@@ -359,7 +358,7 @@ class BaseTomorrowioSensorEntity(TomorrowioEntity, SensorEntity):
             desc.imperial_conversion
             and desc.unit_imperial is not None
             and desc.unit_imperial != desc.unit_metric
-            and not self.hass.config.units.is_metric
+            and self.hass.config.units is IMPERIAL_SYSTEM
         ):
             return handle_conversion(state, desc.imperial_conversion)