Im from Northern Virginia and I will like to know how long I could sit in traffic before the battery dies out. specially on a 100 degree weather.
I don't know exactly how much the Model S draws for running AC and other accessories (my LEAF is a bit over 1kW, so I presume something similar). Before sleep mode was added, you lost about 8mi/day parking it, so I assume the normal draw from the electronics is about that, so even if you assume around 1.5kW it would last sitting running the AC for more than 50 hours -- I suspect far longer than you would be willing to sit there.
EVs and hybrids are far better sitting in traffic -- when people were evacuating Katrina, there were plenty of ICEs that ran out of gas sitting in traffic jams, while Priuses didn't have any trouble.
I believe that is one reason why true Evs are *more* energy efficient in city driving as opposed to highway driving. ICEs use a lot of energy just idling at stop lights.
The long and short of it is you'll fall asleep in your car long before you run out of charge with it "idling".
Also if you look at Tesla's Go Electric page. It shows that the battery lasts longer in warmer (even hotter) weather. So presumably if things were getting desperate range wise you'd still be in an optimal situation if you were willing to turn the A/C off