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


Clarus: The U.S. Federal Highway Administration Nationwide Surface Transportation Weather Observing and Forecasting System Project


For years, state DOTs have invested in Environmental Sensor Stations (ESS) primarily in support of winter maintenance activities. Most ESS, which are field components of Road Weather Information Systems (RWIS), have one or more sensors to measure atmospheric, pavement or water level conditions. While RWIS have become an integral part of winter maintenance operations, the ability to fully utilize these data for other applications is often hampered by suboptimal system design. The FHWA Road Weather Management program, in conjunction with the ITS Joint Program Office, recognized that disparate state investments could be better utilized if they were standardized and made available from one location. FHWA responded with a new initiative called Clarus ? the nationwide surface transportation weather observing and forecasting system. The objective of Clarus is to reduce the impact of adverse weather for all road and transit users and operators by designing and demonstrating an integrated road weather observational network and data management system, and establishing a partnership to facilitate deployment nationwide. This paper describes the Clarus Initiative, its implementation phases and the associated research agenda.


2006 PIARC International Winter Road Congress; FHWA and Mitretek Systems. For an electronic copy of this resource, please direct your request to

Date: 2005


Pisano, Pol, Stern, Goodwin


Road Weather Information System (RWIS)
Weather information
Observing network

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