From what I know the car went off the road and tried to get back on to his lane.  This caused the car to get out of control and went sideways at a 14 degree direction before the collision. 

yes the slope of the street heading south is S=1.45% down and the cross slope of the street is actually S=2.86% to the east from the west edge of pavment.

yes the car went outside of the pavment onto dirt shoulder which has a slope of around S=13% EAST