wind chill factor

We woke up to a beautiful sunny day, the outdoor thermometer at 20 F (-7 C), and off we went on our morning walk. But I nearly froze to death, couldn't get home fast enough. That's when I learned the wind chill factor put the temperature at -11 F (-24 C)!!!
I'm so grateful for my warm home. And I even fed the little beggar at my back door.