DRIVING BLIND Weather-Related Vision Hazards and Fatal Motor Vehicle Crashes

Visibility-related weather hazards have significant impacts on motor vehicle operators because of decreased driver vision, reduced roadway speed, amplified speed variability, and elevated crash risk. This research presents a national analysis of fog-, smoke-, and dust storm-associated vehicular fatalities in the United States. Initially, a database of weather-related motor vehicle crash fatalities from 1994 to 2011 is constructed from National Highway Traffic Safety Administration data. Thereafter, spatiotemporal analyses of visibility-related (crashes where a vision hazard was reported at time of event) and vision-obscured (driver's vision was recorded as obscured by weather, and a weather-related vision hazard was reported) fatal vehicular crashes are presented. Results reveal that the annual number of fatalities associated with weather-related, vision-obscured vehicular crashes is comparable to those of more notable and captivating hazards such as tornadoes, floods, tropical cyclones, and lightning. The majority of these vision-obscured crash fatalities occurred in fog, on state and U.S. numbered highways, during the cool season and during the morning commuting hours of 0500 to 0800 local time. Areas that experience the greatest frequencies of vision-obscured fatal crashes are located in the Central Valley of California, Appalachian Mountain and mid-Atlantic region, the Midwest, and along the Gulf Coast. From 2007 to 2011, 72% of all vision-obscured fatal crashes occurred when there was no National Weather Service weather-related visibility advisory in effect. The deadliest weather-related visibility hazard crashes during the period are exhibited, revealing a spectrum of environmental and geographical settings that can trigger these high-end events.