View article

Various studies on negative effects of rainfall on travel demand and accidents are well documented. However, there are fewer studies on the effect of weather on capacity. As capacity can only be measured on a short section with high traffic flow and it demands more localised weather information which are not easy to collect. The aim of this paper is to determine the effects of rain on capacity and speed and the effects of daylight on capacity. Traffic data from the Tokyo Metropolitan Expressway (MEX) and weather data from the Tokyo Sewerage Bureau’s radar rain gauge system (AMESH) are used. From the analysis of 5 highly congested sections of MEX, the effects of rain on capacity and speed are demonstrated. Further analysis of the capacity during the morning peak of the winter and summer months show a reduction in capacity due to effects of daylight.