We understand you meant to be kind in taking your dog with you today, but you could be risking his life.On a hot summer day the inside of a car heats very quickly. On an 85 F (30 C) degree day, for example, the temperature inside your car - with the windows slightly opened - will reach 102 F (39 C) degrees in 10 minutes. In 30 minutes it will go up to 120 F (49 C) degrees. On warmer days it will go even higher.
A dog's normal body temperature is 101.5 to 102.2 degrees Fahreheit. A dog can withstand a body temperature of 107 - 108 degrees for only a very short time before suffering irreparable brain damage - or even death. The closed car interferes with the dog's normal cooling process; that is, evaporation through panting.
If your dog is over come by heat exhaustion, you can give immediate first aid by immersing him or her in cold water until body temperature is lowered.