Road Weather Management Program
photos of lightning, trucks plowing snow, an empty road before a storm, and an evacuation
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Best Practices for Road Weather Management Version 2.0


Testing the Adverse Visibility Information System Evaluation (ADVISE): Safer Driving in Fog


There are many advisory systems to warn drivers of fog. However, warning drivers that there is fog ahead does not instruct them on what to do. During the 1995-2000 winter seasons, a new technology known as the Adverse Visibility Information System Evaluation (ADVISE) was tested. ADVISE uses visibility sensors to determine current sight distance and corresponding safe speed for the prevailing conditions. DMS instruct drivers of safe speed. This research measures the effectiveness of the system in reducing the variability between speeds. ADVISE successfully reduced speed variability by an average of 22 percent.


81st Transportation Research Board (TRB) Annual Meeting; University of Utah, Traffic Laboratory. For an electronic copy of this resource, please direct your request to

Date: 2002


Perrin Jr, Martin, Coleman


Traffic management
Speed management
Dynamic Message Sign (DMS)
Intelligent Transportation Systems (ITS)
Traveler information

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