Displayed via a layered Google map, WeatherShare aggregates weather and road conditions to help agencies better warn residents and plan their response to snow, ice, and other events. Photo: Caltrans
Displayed via a layered Google map, WeatherShare aggregates weather and road conditions to help agencies better warn residents and plan their response to snow, ice, and other events. Photo: Caltrans

By Jenni Spinner

GOAL: Improve situation assessment, incident recognition, and response by aggregating weather and road condition data from 3,200 sources
OWNER: California DOT (Caltrans)
COST: $506,939
FUNDING: Caltrans


    Phase 1: 2003 – 2006
    Phase 2: 2006 – 2009
    Phase 3: estimated start date July 2011

Severe weather can always wreak havoc, but especially when an operation is ill-prepared. A program launched by the California DOT (Caltrans) is working to diminish nature's damaging effects by helping public agencies better prepare for blizzards, gale-force winds, and ice storms.

WeatherShare aggregates weather and forecast data — i.e., air temperature, atmospheric pressure, average wind speed and direction, fuel moisture and temperature, maximum wind gust speed, precipitation, relative humidity, visibility, etc. — from across the state, then disseminates that information graphically at www.weathershare.org.

Before the tool was developed, emergency responders gathered and analyzed relevant data from several sources, which was tedious and time-consuming. WeatherShare complements Caltrans' road weather information system (RWIS) network of more than 100 sites by retrieving and incorporating sensor readings from several thousand other weather stations as well as data from the National Weather Service's Meteorological Assimilation Data Ingest System (MADIS) and the University of Utah's Mesowest.

“Having accurate and up-to-date information is essential for maintenance staff and emergency first responders to keep the roads safe and to respond to incidents,” says Ian Turnbull, chief of ITS Engineering and Support for Caltrans District 2.

The idea of developing a single repository for weather and road condition data came from Caltrans' Innovation Team (I-Team). Created to foster and implement solutions, I-Team works with partners to develop methods, materials, and technologies that enable the agency to provide the most effective services and resources possible. The agency's Department of Research and Innovation contracted with the Western Transportation Institute at Montana State University to develop WeatherShare in 2003.

  • Phase 1, the prototype, covered seven counties in Northern California and received a thumbs-up from both the project panel and end users.
  • Phase 2 expanded the Web site to include the entire state — with emphasis on 16,600 miles of state and federal highways — and sources of recent and expected weather conditions. Three-level quality control procedures were implemented to flag questionable sensor readings. Other features include mapping National Digital Forecast Database forecasts to highway mileposts, and using combinations of data to display alert conditions (i.e., ice, snow, or wind warnings). A survey conducted in 2009 elicited unanimously positive feedback.
  • Phase 3 will implement the tool throughout Caltrans, and investigate how to integrate weather data into regional 511 traveler information systems.
  • Enhancements in the works

    In addition to expanding WeatherShare's range, Caltrans is expanding its scope of services.

    For example, wind is a problem in much of the state. When they see that a severe wind event is forecasted or occurring — and where the high winds are — employees determine what highways are in peril and notify motorists by activating a warning via the agency's Highway Advisory Radio and Changeable Message Sign network. Employees also can look ahead to see when the wind is expected to diminish, and perform other tasks until an updated advisory is required.

    As development continues, Caltrans and the I-Team are looking for other ways to enhance functionality.

    An aviation application is in progress to provide similar data for rural airfields and heliports. Caltrans and the Oregon DOT are looking into adding elements such as closed-circuit television images and changeable messages to provide one integrated Web site for both DOT personnel and the public. A research effort is under way to expand an integrated site to include Washington and Nevada as well as California.

    “Information about the system has been getting out,” says Caltrans Marketing and Outreach Specialist Rebecca Boyer, “and its use continues to grow.”

    — Spinner (jspinwrites@gmail.com) is a Chicago-based freelance writer and a former editor of PUBLIC WORKS.