Road Weather Management Program
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Best Practices for Road Weather Management Version 2.0


Inclement Weather and Traffic Flow at Signalized Intersections: A Case Study from Northern New England


The study had two main objectives: to assess the impact of inclement weather on traffic flow parameters at signalized intersections in northern New England, and to evaluate the likely operational benefits of implementing "special" timing plans for inclement weather conditions. To do this, a signalized intersection in Burlington, Vermont was selected and video-taped over a period of three months. The weather/road surface conditions were categorized into six different classes, and values for the saturation headways and startup lost times were collected and statistically analyzed. A signalized collector was then selected as a case study for evaluating the likely benefits of developing special timing plans for inclement weather. The study revealed that inclement weather has a significant impact on the saturation headways, particularly once slushy conditions start. Startup lost time, however, does not appear to be significantly impacted by inclement weather. The study also showed that there are benefits to be expected from implementing "special" signal plans for inclement weather.


83rd Transportation Research Board (TRB) Annual Meeting, University of Vermont and University of Conneticut. For an electronic copy of this resource, please direct your request to

Date: 2004


Agbolosu-Amison, Sadek, ElDessouki


Pavement condition
Traffic signal
Traffic modeling

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