Impact of cold and snow on temporal and spatial variations of highway traffic volumes

Presented in this paper is an investigation of the impact of cold and snow on daily and hourly traffic volume variations with detailed considerations to the highway type and location. Regression models are developed to relate the daily and hourly traffic volumes with categorized cold and total snowfall. The study results indicate that the impact of cold and snow on traffic volume varies with day of the week, hour of the day and the type of highway. The commuter roads experience lowest reductions in traffic volume due to cold (up to 14%) while the recreational roads experience highest reduction (up to 31%). Impact of cold on off-peak hours (−10% to −15%) is generally higher than peak hours (−6% to −10%) for commuter roads and an opposite pattern is observed for recreational roads (peak hour reductions of 30–58% and off-peak hour reductions of 18–30%). A clear indication of reduction in traffic volume due to snow is also observed for all types of highways. A detailed investigation is also carried out in this study to illustrate the usefulness of the developed weather models in the context of missing traffic data imputations.