Estimation of road capacity and free flow speed for urban roads under adverse weather conditions

This work aims to estimate changes in traffic characteristics of urban roads in dependence of adverse weather conditions like rain and snow. Investigated traffic characteristics are capacity and free flow speed which are elementary for describing the performance of traffic networks and setting up macroscopic traffic models. The methods are based on aggregated flow and speed measurements from local sensors. Results show a significant reduction of road capacity and free flow speed in dependence of intensity and type of precipitation.