Addison receives new weather radar technology

By ELIZABETH KNIGHTEN, Neighborsgo

ROSE BACA/neighborsgo staff photographer

Mark Acevedo, director of general services for the town of Addison, stands next to the town's recently installed Collaborative Adaptive Sensing of the Atmosphere radar unit. The unit scans the low levels of the atmosphere for severe weather, a view of developing storms that the long-range NEXRAD radar units can't provide.

Unpredictable weather is no stranger to Texans, who know that conditions can change with little notice.

It’s something the town of Addison has experienced firsthand.

Stormy weather has occasionally affected annual events such as Oktoberfest and Kaboom Town, said city manager Ron Whitehead.

Now the town is getting a cutting-edge tool to give residents an additional level of warning during turbulent weather.

Earlier this month, Addison became the fourth location in North Texas and the first in Dallas County to install a CASA radar unit. CASA (Collaborative Adaptive Sensing of the Atmosphere) units spot storm levels that are close to the ground, said Tom Bradshaw, a meteorologist with the National Weather Service.

Casa Engineering Research Center for Collaborative Adaptive Sensing of the Atmosphere runs the CASA radar. The University of Massachusetts Amherst is the project’s lead institution.

The CASA units provide a distinct advantage, Bradshaw said.

“They see the very, very low parts of the storm that we often miss because we simply don’t have a radar that’s close enough to the action,” Bradshaw said.

Mark Acevedo, Addison’s director of general services, describes the unit as “the next generation of Doppler radar.” Three others in the region are located in Denton at the University of North Texas, the University of Texas at Arlington and in Midlothian.

The North Central Texas Council of Governments approached Addison on behalf of CASA in December 2011. Addison Fire Chief John O’ Neal says the location of the town was a contributing factor in its getting the radar, which cost $25,000 to install. The radar, which will cost the city about $500 a month for its fiberoptic network, works in unison with the three other radars.

“It’s geographical, but it’s also based on where the other radars in the network and the overlap that we can get from those because we like to have 30 percent overlap with the radars,” said Amanda Everly, emergency preparedness technical specialist for NCTCOG.

Everly said the region currently houses a Dallas-Fort Worth NEXRAD system that covers more than the 16 counties that fall within the organization. The system sits on the Johnson and Tarrant county line at Fort Worth Spinks Airport. But it has limitations.

“The radar beam, it just keeps going up in the air. It’s a straight line, so as you get farther away, you miss quite a bit of weather that actually happens on the ground,” Everly said.

The CASA radars are placed 30 kilometers apart and provide a smart scan, focusing on a storm and following the worst part to provide continuous updates, she said.

“You get quite a bit of overlap in the radars. They’re faster updating,” she said. “Where the NEXRAD updates every five to six minutes, these radars are going to update every one minute, which is extremely important when you have a severe storm coming through.”

Addison’s unit is currently being fine-tuned by CASA. It will be fully commissioned by the end of March, Acevedo said. It is also monitored remotely by CASA and the NWS.

The radar weighs 375 pounds, and its control cabinet weighs 1,100 pounds, Acevedo said.

“We didn’t buy the radar, but we support it. We paid for all of the installation costs associated with it and the ongoing communications cost on an annual basis because it has to have obviously data network tied to it to send all of the information back to the National Weather Service, so that cost is being borne by the city on an ongoing basis,” Acevedo said.

The town initially thought the cost would be $45,000 to $50,000, Acevedo said. The new design of the radar, which did not require a radome, air conditioning unit inside the radome, or wiring and labor, helped to lower the cost of the system.

NCTCOG received eight donated radars, Everly said. It hopes to have one up in Cleburne and one in northwest Fort Worth by storm season and all eight by the end of the year, Everly said.

“At that point we will look at whether we just want to continue running those eight or more than likely we will continue to expand the networks,” she said. “We’re hoping to have 18 to 20 radars within the North Central Texas Council of Governments region ultimately.”

Whitehead, the city manager, recalls how chaotic a storm can be in Addison.

The threat of straightline winds at the 2013 Oktoberfest forced a tent to be evacuated, he said. He also recalled a KaboomTown! celebration in the Village on the Parkway, where guests were asked to leave because of the threat of bad weather.

“The announcer got on the stage and said ‘The city manager of Addison says you need to get in your cars because of bad weather,’ so everybody started booing,” Whitehead said. “But they did as we asked them to do, got in their cars and really about 20 minutes later we had 60-mile-an-hour straightline winds, and I had folding chairs flying at my head.”