Quote Originally Posted by Jun aka Pekto
Probably not even that. Here in Arizona, We'd have the A/C at 3/4 maximum with temperature inside the car an estimated 75F/24C (so cold sometimes we have to turn it down to 1/4) while outside, it's almost 120F/49C.

It'll have to take something solid like direct hit from a pebble to crack a windshield.
is the A/C directed at the windshield?