Visibility is often a problem when driving a car. Many things can reduce visibility. Some of them are man-made and others are caused by nature.
Driving in autumn is an example of the latter. Late in the day, the sun is so low in the sky that it can be blinding. While it is most dangerous for drivers, it can be a problem for cyclists, as well.
Cyclists can be blinded to the extent that they cannot see oncoming traffic. Knowing what to do under such circumstances is not always easy.