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Best Practices for Road Weather Management Version 2.0

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Title:

Modifying Signal Timing During Inclement Weather

Abstract:

This paper examines traffic parameters for developing signal timings during inclement weather conditions. Traffic flow data is collected over a range of seven inclement weather severity conditions at two intersections for the 1999/2000 winter season. The data indicates that the largest decrease in vehicle performance occurs when snow and slush begins to accumulate on the road surface. Saturation flows decrease by 20 percent, speeds decrease by 30 percent, and start-up lost times increase by 23 percent. UDOT is now developing and implementing modified inclement weather coordinated signal timing plans for the major signalized corridors in the Salt Lake Valley. The determination of when to implement an inclement weather signal timing plan is based on four general criteria: storm severity, projected duration, area of influence and immediately projected running speeds. With these considerations, traffic engineers can determine whether to implement an inclement weather signal timing plan.

Source(s):

80th Transportation Research Board Annual Meeting, University of Utah

https://journals.sagepub.com/doi/10.3141/1748-08

Date: 2001

Author:

Perrin Jr, Martin, Hansen

Keywords:


Adverse weather
Snow
Ice/Frost
Pavement condition
Speed
Capacity
Mobility

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