Rain began to fall on a cornfield about 20 miles from University Park as a storm front approached on a cool October night.
A group of Penn State meteorology students huddled in a large truck that looked more like a rolling science station — its antenna towering toward the sky and its large radar dish moving into position. Inside, the students’ faces were illuminated by banks of computer monitors churning out information about the storm.
At their disposal was one of the most sophisticated tools scientists have for getting up close and personal with severe weather — the Doppler on Wheels.
The mobile weather radar is one in a fleet operated by the Center for Severe Weather Research in Colorado, and it’s the envy of storm chasers everywhere. It was a DOW that captured the highest wind speed ever recorded (more than 301 mph during a massive tornado in Oklahoma in 1999), and it’s tackled hurricanes and lake-effect snow, too.
The fleet also has given researchers some of the best data available about severe weather. The information can be used by scientists, including at Penn State, as they work to solve unanswered questions about — among other things — tornadoes.
That’s important because the more researchers know about how tornadoes form, the more advance warning forecasters can give before the potentially deadly storms reach a destination, said Alicia Klees, a Penn State doctoral student studying meteorology.
Klees’ research draws on information gathered by the DOW as the vehicles’ operators chase storms across the country. But this month, she had her first look at the equipment that makes that research possible when one of the trucks pulled in for a two-week stop at Penn State.
“Tornado-chasing field data, a lot of that comes from this exact radar,” Klees said. “It’s used a lot in thunderstorms and tornadoes, so we can get a better understanding of them and increase warning times and things like that.”
Penn State meteorology professors Yvette Richardson and Matthew Kumjian, in the College of Earth and Mineral Sciences, helped bring the DOW to campus for the first time since 2004. When the truck isn’t out chasing storms, it makes educational trips to universities.
And while the impressive vehicle was on display for the community during its stay, it was Penn State students who had a chance to score some research-quality data during several storm events.
The students ran the show when storms rolled through — choosing where to aim the radar and collecting their own data. With that information in hand, they will study what happens during those events and the broader picture of weather systems.
“For them, this is going to be a once-in-a-lifetime opportunity,” Kumjian said. “They get to play with a multi-million dollar jewel. It’s finally clicking, all the stuff we are doing on the chalkboard. Plus we are getting great research-quality data.”
Ashley Ellis, one of the Penn State students who crammed into the DOW and sampled a storm at the rainy cornfield, said she hopes she can someday play a part in increasing warning accuracy.
“There are a lot of unknown things,” Ellis said. “And that’s why we have these trucks, hopefully to go out there and one day find the unknown. The more we understand the starting conditions, the better we’ll be able to predict for hard-hit areas.”
High-tech mobile equipment like the DOW has proven to be important in the quest to learn more about tornadoes. It can be difficult to get a clear picture of the storms with traditional radar, Richardson said.
With traditional radar, “your beam gets wider as it goes out, which means you’re getting a fuzzier and fuzzier picture,” she said. “So the closer you can get to the phenomenon, the crisper. It’s like having more pixels in your image.”
The trucks, too, have evolved over the years since the first DOW rolled out in 1995. More sophisticated radar and banks of internal computers record data like never before and allow real-time streaming of weather observations and forecasts to aid storm chasing.
“It’s really changed how you do storm chasing,” Richardson said. “You have all this information coming in. I remember back when we didn’t even have cellphones. You literally had to stop, find a pay phone and call someone to tell you what the maps look like.”
Thanks in part to the DOW, students like Klees can pore over data collected directly from the path of a tornado in the Midwest, even if the storm doesn’t hit close to home.
“Everyone needs to know something about weather,” Klees said. “It’s incredibly important. Even if we don’t get a lot of tornadoes here, we need to very much pay attention.”