You know the radio will work with the engine off, right? And the fan too! If the car is already warm/cold, the fan will move enough air to keep the car comfortable on all the but hottest/coldest days.
Yes, Atlanta. Only slightly (2* or so) warmer, on average, than DC. And, this time of year would typically have the hottest days. So, I'll stand by my point. If you're idling your car for 20 minutes while eating a Big Mac in April, you're needlessly polluting. Hot days in July and August - I get it, but would prefer you just went inside.
