For this predawn two-vehicle crash, involving a loader crossing the road and a SUV on the through road, the crash site was reported to have been dark with no streetlights. Eyewitnesses variously described crash-scene weather as some combination of mist, fog, or very light rain.

​Dr. Lee was tasked with determining:

  • How did these weather and lighting conditions affect visibility of the striking driver to a crossing loader?
  • What was the visibility of the vehicle operator crossing the road?

Ray Lee’s analysis included: an extrapolation of visibility and weather conditions reported at a nearby National Weather Service station to the crash site; the position of the sun; the visibility attributes of both vehicles, such as the SUV’s headlights, reflectors and the side of the loader itself; how the visibility to these elements was attenuated by the weather; and, a theoretical contrast determination and comparison to the threshold contrast required for detection, taking in to account the driver’s expectancy.

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Featured Expert

Raymond L. Lee, Ph.D.

Dr. Lee is expert in determining weather conditions at a particular location, how weather and visibility conditions affect vehicle collisions, including those involving pedestrians, and how weather events affect other incidents such as property damage and sporting events gone wrong. He has been providing forensic meteorology expertise since 1992.

Raymond L. Lee, Jr., Ph.D. is an expert in assessing site-specific weather history, visibility under different lighting and weather conditions, including cases that involve rain, snow, fog, and nighttime street lighting, as well as those where glare from sunlight or headlights is at issue. He routinely applies his expertise to vehicle collisions, including those involving pedestrians, and to pedestrian slips, trips, and falls. Dr. Lee has extensive experience in forensic meteorology and can draw on a wide range of government and private weather records as part of his investigation of your case.

Dr. Lee has engaged in meteorological research and education for more than 30 years, with the last 22 years spent as a research professor at the U. S. Naval Academy. He has been awarded seven highly competitive grants from the National Science Foundation. He has testified nationally and has researched and written more than 120 technical reports for both civil and criminal cases during the past 22 years. He is a member of the American Meteorological Society and the Optical Society of America.