On a sunny afternoon, a driver turned left from a stop sign and a short distance later struck a pedestrian. The driver claimed that his turn and irregular shadows from city buildings suddenly exposed him to sun glare that prevented him from seeing the pedestrian.

Dr. Raymond Lee, PhD, an expert in meteorology and visibility in adverse weather conditions, was retained on behalf of the plaintiff to evaluate visibility conditions at the time of the incident. As part of his analysis, Dr. Lee calculated:

  1. the angle between the sun and driver’s line of sight and
  2. the amount of sun glare possible at that angle.

Dr. Lee determined that although this glare would have reduced the pedestrian’s contrast, there still would have been enough contrast so that the driver should have detected the pedestrian in time to avoid a collision.


Featured Expert

Raymond L. Lee, Ph.D.

Dr. Lee is an expert in the determination of weather conditions and their effect on vehicle collisions. He has spent over 30 years in meteorological research and education, including the last 20+ years as a research professor at the U.S. Naval Academy.