My wife has 2 small dog like creatures (Chihuahuas) and they are funny this time of year. We will move the gate and open the door, which means time to go outside. They will run at top speed until they hit the deck. At that time they hits the breaks, skid to a stop and give you a WTF look. They quickly take care of business and beat feet to the back door.
If you have a dog, don't leave it outside. Its still below ZERO out there.
Fixed that for you. Single digit temps, windchill well below zero, bring your dog inside whether it lives outside or not.