diff --git a/homeassistant/components/sensor/forecast.py b/homeassistant/components/sensor/forecast.py
index 6222ad4d664..a9783104cd8 100644
--- a/homeassistant/components/sensor/forecast.py
+++ b/homeassistant/components/sensor/forecast.py
@@ -49,6 +49,8 @@ Details for the API : https://developer.forecast.io/docs/v2
 import logging
 from datetime import timedelta
 
+REQUIREMENTS = ['python-forecastio>=1.3.3']
+
 try:
     import forecastio
 except ImportError: