The Humane Society of the United States has some tips on how to keep your four-legged friends safe from the heat. On just an 85-degree day the temperature inside a car even with windows slightly open can reach 102 degrees within 10 minutes. According to the Humane Society, if the humidity is too high, pets are unable to cool themselves and their temperature will skyrocket. Be extra careful with pets with white-colored ears, they are more susceptible to skin cancer and short-nosed pets usually have difficulty breathing. A doghouse does not provide relief from the heat, in fact, according to the Humane Society, it makes it worse.