[header] How to safely keep your dog in the yard [title] Check the weather. [step] Extreme heat or extreme cold can potentially kill dogs left outdoors. Some dog breeds, like pugs, are particularly sensitive to extremes in temperature. 
You should never leave a dog unattended outdoors for prolonged periods of time, especially if the weather is going to be very hot or very cold. Humidity and wind chill can also endanger a pet.