5 PM is a bit early for sun blinding him
That depends on the date and whether you’re westbound.
On a flat road. If his windshield was dirty and driver was facing a setting sun on a slight upward incline he could have been blinded by the sun. If the driver was on a slightly wet road, facing the sun, the suns reflection off the road and sunlight going straight into drivers eyes could have nearly blinded driver..happened to me...