ILLINOIS (NewsFirst) — Remote weather stations are an important part of IDOT’s Roadway Weather Information System, with new sites and innovations a hot topic for frigid temperatures. Because the stations help provide information about road conditions so the public can make educated travel plans and assist IDOT maintenance teams in plowing and other cleanup efforts during bad weather, expanding and fine-tuning the information they provide is beneficial to all Illinoisans.

RWIS towers that motorists see on the side of the road are generally connected to hockey-puck shaped sensors embedded in the pavement. The sensors measure important data, such as pavement temperature, dew point, relative humidity, precipitation and road surface conditions.

Once collected, the information is uploaded to sites like and for the public, as well as IDOT’s internal weather provider site, which uses the data to inform winter weather preparation and help determine the department’s response to winter storms. IDOT has 53 RWIS locations throughout the state.

“When an RWIS site is located within a construction project, we generally try to update or upgrade it,” said Weight Enforcement Engineer Keith Donovan. “Depending on the scope of the project, new sensors could be installed, or an all-new system could be installed.”

In active stations, ongoing maintenance addresses issues as they arise, with checks prior to snow and ice season.

“We have a maintenance support contract for the RWIS sites,” Donovan said. “When something has issues, we let our contractor know, and they will determine what needs to be done. Additionally, before the winter season, the maintenance contractor goes out for annual preventive maintenance service to have the sites ready for winter weather.”

In the future, the department plans to add more sites, working with the districts to determine prime locations. The use of mini-RWIS stations also is being considered. Mini stations would feature a smaller footprint and run on solar power as opposed to an AC power connection. These stations typically allow for a smaller enclosure and can be mounted to a pole.

Other innovations are also underway in northern and central Illinois.

“We are conducting a study in districts 2, 3 and 6 with mobile RWIS sensors that are attached to plow trucks and smaller light duty trucks when they are out responding to an event,” Donovan said. “This allows us to see road conditions in real time and adjust our approach to the storm if necessary.”