diff --git a/homeassistant/components/weather/darksky.py b/homeassistant/components/weather/darksky.py
index 17e3cbbcf14..d5cbcb4785a 100644
--- a/homeassistant/components/weather/darksky.py
+++ b/homeassistant/components/weather/darksky.py
@@ -232,4 +232,6 @@ class DarkSkyData:
     @property
     def units(self):
         """Get the unit system of returned data."""
+        if self.data is None:
+            return None
         return self.data.json.get('flags').get('units')