SULLIVAN—Just as Wisconsin’s severe weather season arrives, the Doppler radar at the National Weather Service facility in Sullivan has undergone an upgrade.

The massive piece of weather technology is back up and running after being down for 10 days last month, once again dominating the sky near Rome Mill Pond as it provides invaluable information to NWS meteorologists about the structure and severity of storms.

The weather service’s KMKX WSR-88D radar was being upgraded by technicians in April, according to facility officials.

The techs refurbished and replaced the radar’s pedestal, called by NWS officials “one of the most critical components of the radar.” They said the pedestal is necessary for antenna rotation and positioning to capture data in all directions.

“The components are extremely heavy and require the radome to be removed by crane and replaced when the work is completed,” the NWS said. “The radar and pedestal were designed to last 25 years, and this radar has exceeded its life span. This activity is necessary to keep the radar functioning for another 20 years or more.”

According to the NWS, the pedestal refurbishment is the third major project of the NEXRAD Service Life Extension Program, a series of upgrades that will keep the nation’s radars viable into the 2030s. The weather service, the U.S. Air Force and the Federal Aviation Administration are investing $135 million in the eight-year program.

“The first project was the installation of the new signal processor, and the second project was the refurbishment of the transmitter. The fourth project will be the refurbishment of the equipment shelters. The Service Life Extension Program will be complete in 2023,” the NWS said.

During the downtime, adjacent radars were available, including ones in Milwaukee, Green Bay, La Crosse, the Quad Cities of Illinois and Iowa, and Chicago/Romeoville, Illinois.

According to the Earth Observing Laboratory, Doppler radar is a specific type of radar that uses the Doppler effect to gather velocity data from the particles like rain, snow and dust.

The “Doppler effect” that is used by the radar in Sullivan and in others around the world, was named after the Austrian physicist, Christian Doppler, who discovered it.

“(A) Doppler radar transmits a signal that gets reflected off raindrops within a storm. The reflected radar signal is measured by the radar’s receiver with a change in frequency. That frequency shift is directly related to the motion of the raindrops,” the EOL stated. This helps in the tracking and measuring of storms.

The radar in Sullivan is part of a network of 159 operational radars, according to the weather service. The Radar Operations Center in Norman, Oklahoma, provides life cycle management and support for all WSR-88D radars.

According to Andy Boxell, lead forecaster in Sullivan, work was completed April 7. The entire upgrade process took about 10 days, he said.

“The project went exactly as expected,” Boxell said. “The crew doing the work is contracted through the National Weather Service’s Radar Operations Center, and they have the process pretty well perfected at this point. There are some planned updates to a few of the small shelter buildings at the base of the radar that house some equipment, but the refurbishments on the actual radar itself are complete.”