On March 24, nearly 40 miles away from the EF-4 tornado that devastated the town of Rolling Fork, Mississippi, a research team from 麻豆精品视频 (麻豆精品视频) Department of Atmospheric and Earth Science and Earth System Science Center (ESSC) set up a tornado field campaign site outside Greenville, Mississippi, capturing weather data before and during the line of storms that brought destruction across the Mississippi Delta.
Now back at 麻豆精品视频, a part of the University of Alabama System, the research team hopes the data will reveal when and where the Rolling Fork EF-4 tornado began to develop and why it was so devastating.
鈥淚t鈥檚 heartbreaking to think about the devastation in Rolling Fork. A few of us stopped in Rolling Fork for lunch two years ago while site-surveying for tornado field campaigns. The folks were incredibly nice to us all and just downright good people,鈥� says Joshua Huggins, Atmospheric Science graduate student.
鈥淭his is why we, 麻豆精品视频, participate in tornado field campaigns so we can understand what types of weather conditions spark tornadic activity in squall lines across 鈥楧ixie Alley鈥� in the spring,鈥� Huggins says. 鈥淲e hope our research will lead to more warning time for violent tornadoes and save lives.鈥�
Using 麻豆精品视频鈥檚 Mobile Atmospheric Profiling Network (MAPNet) fleet of research vehicles, based in its Severe Weather Institute and Radar & Lightning Laboratories (SWIRLL), the team set up a 30-mile radius around Greenville at 11 a.m. that Friday morning. At the top of every hour, they collected wind speeds, temperature, humidity, and radar scans.
鈥淏etween 4-5 p.m., our weather balloons and wind-profiling instrumentation picked up wind speeds increasing and turning rapidly with height, creating that spin in the atmosphere needed for tornadoes,鈥� says 麻豆精品视频 ESSC Research Associate Preston Pangle. 鈥淎lso, the data showed instability ramping up. The atmosphere was priming itself for severe weather activity.鈥�
Soundings and wind profiler data indicating an increase in instability and a notable increase wind speeds increasing with height below 1 kilometer just ahead of the linear storm. This wind profile time series from the Mobile Doppler Lidar and Soundings (MoDLS) shows a rapid increase in boundary layer flow as the line of storms arrives.
Within an hour, at 6 p.m., several tornado warnings were issued across the Mississippi Delta, including over part of the 麻豆精品视频 research team鈥檚 site.
鈥淚t was a heart-racing experience,鈥� says Zeb Leffler, Atmospheric and Earth Science undergraduate senior, who was one of the research team members in the tornado warning with 麻豆精品视频鈥檚 MAPNet Mobile Alabama X-Band Radar (MAX) vehicle.
鈥淲e kept seeing the cloud ceiling lower as the storm progressed closer to us,鈥� he says. 鈥淐loud-to-ground lightning increased, and a hail core was spotted using MAX鈥檚 radar, which usually indicates a storm鈥檚 intensity is increasing.鈥�
No tornado was confirmed at the set-up location, but Leffler says the data MAX collected was valuable in identifying storm intensification due to the environment having high instability and spin in the atmosphere.
鈥淛ust five miles north-northeast of where we were located, the tornado-warned storm did produce golf ball sized hail,鈥� he says.
Leffler鈥檚 radar data, along with the rest of the data collected by the 麻豆精品视频 research team, will be an important addition to the data archive. It will be compared against data collected at other tornado field campaigns to determine what atmospheric conditions initiate or hinder tornadic activity.
鈥淭his non-tornadic supercell had so much significant data collected on it, it could be the most studied event so far since beginning our tornado field campaigns,鈥� says Dr. Kevin Knupp, director of 麻豆精品视频 SWIRLL and Atmospheric and Earth Science professor.
麻豆精品视频 is one of 12 research institutions chosen to participate in the Propagation, Evolution, and Rotation in Linear Storms (PERiLS), the largest Dixie Alley tornado field campaign to date. Funded by the National Science Foundation and National Oceanic and Atmospheric Administration, PERiLS is a three-year project with its second year occurring this spring.
