diff --git a/homeassistant/components/metoffice/const.py b/homeassistant/components/metoffice/const.py
index 0b275f301cd..e413b102898 100644
--- a/homeassistant/components/metoffice/const.py
+++ b/homeassistant/components/metoffice/const.py
@@ -2,6 +2,7 @@
 from datetime import timedelta
 
 from homeassistant.components.weather import (
+    ATTR_CONDITION_CLEAR_NIGHT,
     ATTR_CONDITION_CLOUDY,
     ATTR_CONDITION_EXCEPTIONAL,
     ATTR_CONDITION_FOG,
@@ -37,6 +38,7 @@ MODE_DAILY = "daily"
 MODE_DAILY_LABEL = "Daily"
 
 CONDITION_CLASSES = {
+    ATTR_CONDITION_CLEAR_NIGHT: ["0"],
     ATTR_CONDITION_CLOUDY: ["7", "8"],
     ATTR_CONDITION_FOG: ["5", "6"],
     ATTR_CONDITION_HAIL: ["19", "20", "21"],
@@ -47,7 +49,7 @@ CONDITION_CLASSES = {
     ATTR_CONDITION_RAINY: ["9", "10", "11", "12"],
     ATTR_CONDITION_SNOWY: ["22", "23", "24", "25", "26", "27"],
     ATTR_CONDITION_SNOWY_RAINY: ["16", "17", "18"],
-    ATTR_CONDITION_SUNNY: ["0", "1"],
+    ATTR_CONDITION_SUNNY: ["1"],
     ATTR_CONDITION_WINDY: [],
     ATTR_CONDITION_WINDY_VARIANT: [],
     ATTR_CONDITION_EXCEPTIONAL: [],
diff --git a/tests/components/metoffice/test_weather.py b/tests/components/metoffice/test_weather.py
index 21b2196804c..76e01b638c3 100644
--- a/tests/components/metoffice/test_weather.py
+++ b/tests/components/metoffice/test_weather.py
@@ -231,7 +231,7 @@ async def test_two_weather_sites_running(hass, requests_mock, legacy_patchable_t
         weather.attributes.get("forecast")[18]["datetime"]
         == "2020-04-27T21:00:00+00:00"
     )
-    assert weather.attributes.get("forecast")[18]["condition"] == "sunny"
+    assert weather.attributes.get("forecast")[18]["condition"] == "clear-night"
     assert weather.attributes.get("forecast")[18]["temperature"] == 9
     assert weather.attributes.get("forecast")[18]["wind_speed"] == 4
     assert weather.attributes.get("forecast")[18]["wind_bearing"] == "NW"