As traffic congestion increases, the duration of the morning, afternoon or noontime “rush hour,” when traffic volume is at its highest, also increases. This phenomenon is known as “peak spreading.” It can be measured through the use of a K factor – the proportion of 24-hour volume that occurs during the peak hour.

This research will develop an approach to forecast the extent of this peak spreading for urban locations, starting with VDOT’s Northern Virginia District as a case study. Such forecasts will be based not only on predicted volume characteristics but also socioeconomic data. Ways of describing peak spreading besides the K factor may be considered