I have to agree that the heat is not a factor. Possibly mirage as previously stated.
And as for shooting across a public road. In PA the game law states that you CAN shoot across a public road if the path of the bullet is above the flow of traffic.
From the PGC site:
Road Hunting
It is unlawful to (1) hunt from a vehicle; (2) shoot at a turkey on a public road or right-of-way open to public travel; (3) shoot across a road unless the line of fire is high enough to preclude any danger to road users; and (4) alight from a vehicle and shoot at a turkey until the shooter is at least 25 yards from the traveled portion of the roadway.